You must not use ; at the end of each line!! Use a , (comma) instead, except on the last line (before the )).
Also, for the NOT NULL, don't define an explicit constraint - on the other hand, for the default value for join_date, you should define an explicit constraint.
And the expression to use for that default constraint should be SYSDATETIME() for T-SQL - not SYSDATE() ....
create table member
(
member_id member(10)
constraint member_member_id_pk PRIMARY KEY,
last_name varchar2(25) NOT NULL,
join_date DATE NOT NULL
constraint df_member_join_date DEFAULT (SYSDATETIME())
)
And last but not least - this here is the official MSDN documentation for CREATE TABLE where you find all these details - and more - please consult it next time you need to know something like this!