I have installed PHP version 7.3.33, composer 1.1 and running multiple laravel 7.x projects.
Now I am trying to install two different Laravel Projects. One with Laravel 9 and the other with 7.x.
If I update the PHP and Composer Version, it will create issues in existing laravel 7.x projects.
Is there any way to Upgrade/ make compatible the old laravel projects to composer 2 and new PHP version.
Problem 1
- This package requires php ^8.0.2 but your PHP version (7.4.29) does not satisfy that requirement.
Problem 2
- Installation request for laravel/framework v9.1.0 -> satisfiable by laravel/framework[v9.1.0].
- laravel/framework v9.1.0 requires php ^8.0.2 -> your PHP version (7.4.29) does not satisfy that requirement.
Problem 3
- Installation request for league/flysystem 3.0.8 -> satisfiable by league/flysystem[3.0.8].
- league/flysystem 3.0.8 requires php ^8.0.2 -> your PHP version (7.4.29) does not satisfy that requirement.
Problem 4
- Installation request for psr/log 3.0.0 -> satisfiable by psr/log[3.0.0].
- psr/log 3.0.0 requires php >=8.0.0 -> your PHP version (7.4.29) does not satisfy that requirement.
Problem 5
- Installation request for psr/simple-cache 3.0.0 -> satisfiable by psr/simple-cache[3.0.0].
- psr/simple-cache 3.0.0 requires php >=8.0.0 -> your PHP version (7.4.29) does not satisfy that requirement.
Problem 6
- Installation request for symfony/console v6.0.3 -> satisfiable by symfony/console[v6.0.3].
- symfony/console v6.0.3 requires php >=8.0.2 -> your PHP version (7.4.29) does not satisfy that requirement.
Problem 7
- Installation request for symfony/css-selector v6.0.3 -> satisfiable by symfony/css-selector[v6.0.3].
- symfony/css-selector v6.0.3 requires php >=8.0.2 -> your PHP version (7.4.29) does not satisfy that requirement.
Problem 8
- Installation request for symfony/deprecation-contracts v3.0.0 -> satisfiable by symfony/deprecation-contracts[v3.0.0].
- symfony/deprecation-contracts v3.0.0 requires php >=8.0.2 -> your PHP version (7.4.29) does not satisfy that requirement.
Problem 9
- Installation request for symfony/error-handler v6.0.3 -> satisfiable by symfony/error-handler[v6.0.3].
- symfony/error-handler v6.0.3 requires php >=8.0.2 -> your PHP version (7.4.29) does not satisfy that requirement.
Problem 10
- Installation request for symfony/event-dispatcher v6.0.3 -> satisfiable by symfony/event-dispatcher[v6.0.3].
- symfony/event-dispatcher v6.0.3 requires php >=8.0.2 -> your PHP version (7.4.29) does not satisfy that requirement.
Problem 11
- Installation request for symfony/event-dispatcher-contracts v3.0.0 -> satisfiable by symfony/event-dispatcher-contracts[v3.0.0].
- symfony/event-dispatcher-contracts v3.0.0 requires php >=8.0.2 -> your PHP version (7.4.29) does not satisfy that requirement.
Problem 12
- Installation request for symfony/finder v6.0.3 -> satisfiable by symfony/finder[v6.0.3].
- symfony/finder v6.0.3 requires php >=8.0.2 -> your PHP version (7.4.29) does not satisfy that requirement.
Problem 13
- Installation request for symfony/http-foundation v6.0.3 -> satisfiable by symfony/http-foundation[v6.0.3].
- symfony/http-foundation v6.0.3 requires php >=8.0.2 -> your PHP version (7.4.29) does not satisfy that requirement.
Problem 14
- Installation request for symfony/http-kernel v6.0.4 -> satisfiable by symfony/http-kernel[v6.0.4].
- symfony/http-kernel v6.0.4 requires php >=8.0.2 -> your PHP version (7.4.29) does not satisfy that requirement.
Problem 15
- Installation request for symfony/mailer v6.0.3 -> satisfiable by symfony/mailer[v6.0.3].
- symfony/mailer v6.0.3 requires php >=8.0.2 -> your PHP version (7.4.29) does not satisfy that requirement.
Problem 16
- Installation request for symfony/mime v6.0.3 -> satisfiable by symfony/mime[v6.0.3].
- symfony/mime v6.0.3 requires php >=8.0.2 -> your PHP version (7.4.29) does not satisfy that requirement.
Problem 17
- Installation request for symfony/process v6.0.3 -> satisfiable by symfony/process[v6.0.3].
- symfony/process v6.0.3 requires php >=8.0.2 -> your PHP version (7.4.29) does not satisfy that requirement.
Problem 18
- Installation request for symfony/routing v6.0.3 -> satisfiable by symfony/routing[v6.0.3].
- symfony/routing v6.0.3 requires php >=8.0.2 -> your PHP version (7.4.29) does not satisfy that requirement.
Problem 19
- Installation request for symfony/service-contracts v3.0.0 -> satisfiable by symfony/service-contracts[v3.0.0].
- symfony/service-contracts v3.0.0 requires php >=8.0.2 -> your PHP version (7.4.29) does not satisfy that requirement.
Problem 20
- Installation request for symfony/string v6.0.3 -> satisfiable by symfony/string[v6.0.3].
- symfony/string v6.0.3 requires php >=8.0.2 -> your PHP version (7.4.29) does not satisfy that requirement.
Problem 21
- Installation request for symfony/translation v6.0.3 -> satisfiable by symfony/translation[v6.0.3].
- symfony/translation v6.0.3 requires php >=8.0.2 -> your PHP version (7.4.29) does not satisfy that requirement.
Problem 22
- Installation request for symfony/translation-contracts v3.0.0 -> satisfiable by symfony/translation-contracts[v3.0.0].
- symfony/translation-contracts v3.0.0 requires php >=8.0.2 -> your PHP version (7.4.29) does not satisfy that requirement.
Problem 23
- Installation request for symfony/var-dumper v6.0.3 -> satisfiable by symfony/var-dumper[v6.0.3].
- symfony/var-dumper v6.0.3 requires php >=8.0.2 -> your PHP version (7.4.29) does not satisfy that requirement.
Problem 24
- Installation request for nunomaduro/collision v6.1.0 -> satisfiable by nunomaduro/collision[v6.1.0].
- nunomaduro/collision v6.1.0 requires php ^8.0.0 -> your PHP version (7.4.29) does not satisfy that requirement.
Problem 25
- Installation request for spatie/flare-client-php 1.0.2 -> satisfiable by spatie/flare-client-php[1.0.2].
- spatie/flare-client-php 1.0.2 requires php ^8.0 -> your PHP version (7.4.29) does not satisfy that requirement.
Problem 26
- Installation request for spatie/ignition 1.0.5 -> satisfiable by spatie/ignition[1.0.5].
- spatie/ignition 1.0.5 requires php ^8.0 -> your PHP version (7.4.29) does not satisfy that requirement.
Problem 27
- Installation request for spatie/laravel-ignition 1.0.6 -> satisfiable by spatie/laravel-ignition[1.0.6].
- spatie/laravel-ignition 1.0.6 requires php ^8.0 -> your PHP version (7.4.29) does not satisfy that requirement.
Problem 28
- laravel/framework v9.1.0 requires php ^8.0.2 -> your PHP version (7.4.29) does not satisfy that requirement.
- laravel/sail v1.13.4 requires illuminate/console ^8.0|^9.0 -> satisfiable by laravel/framework[v9.1.0].
- Installation request for laravel/sail v1.13.4 -> satisfiable by laravel/sail[v1.13.4].

composer updateinside your project to update thecomposer.jsonversions? For the last case, you should never be able to screw up other projects since you are working in a project context.