How to get an index of a word in string array

I could do it but just inside the if state. I want to bring it outside.

Your code identifies the index correctly, all you need to do now is storing it for use outside the loop.

Make a list of ints, and call Add on it for the matches that you identify:

var indexes = new List<int>();
while (i < words.Length) {
    foreach (string verb in verbs) {
        if (words[i] == verb) {
            int index = i;
            indexes.Add(i);
            break;
        }
    }
    i++;
}

You can replace the inner loop with a call of Contains method, and the outer loop with a for:

for (var i = 0 ; i != words.Length ; i++) {
    if (verbs.Contains(words[i])) {
        indexes.Add(i);
    }
}

Finally, the whole sequence can be converted to a single LINQ query:

var indexes = words
    .Select((w,i) => new {w,i})
    .Where(p => verbs.Contains(p.w))
    .Select(p => p.i)
    .ToList();

Here is an example

var a = "I love you.";
var words = a.Split(' ');
var index = Array.IndexOf(words,"love");
Console.WriteLine(index);

private int GetWordIndex(string WordOrigin, string GetWord)
{
    string[] words = WordOrigin.Split(' ');

    int Index = Array.IndexOf(words, GetWord);

    return Index;
}

assuming that you called the function as GetWordIndex("Hello C# World", "C#");, WordOrigin is Hello C# World and GetWord is C#

now according to the function:

1. string[] words = WordsOrigin.Split(' '); broke the string literal into an array of strings where the words would be split for every spaces in between them. so Hello C# World would then be broken down into Hello, C#, and World.

2. int Index = Array.IndexOf(words, GetWord); gets the Index of whatever GetWord is, according to the sample i provided, we are looking for the word C# from Hello C# World that is then splitted into an Array of String

3. return Index; simply returns whatever index it was located from