HI!

Yes, it is a difference between "good" and "well." Good is an adjective while well is an abverb. Let us look at an example..

1. I am a good student.

Here, good describes what kind of student, I am.

2. I am doing well.

Here, well is an adverb.

You might hear some English speakers say "I am good," but this is incorrect. You are suppose to say "I am well." The word good in the sentence "I am good" is not describing a noun in the sentence, so it is wrong.

You can also use the word "well" as an introducing one, and in this case it doesn't express something good. For example - "Well, I'm not sure this is the gift she would be happy to receive".

what you tell me is right because what it confused me was the answer "I'm good".

Thanks! 

When you learn something new, it is important to practice it so that you remember the rule. Here is a little test so that you can practice when to use good or well. 

http://www.autoenglish.org/prepositions/ForandToExercise.htm

it is very useful and complete! thanks

"Well" is also an adjective meaning "healthy" or "okay", as in "Get well soon!" This is not an adverb suggesting that the action of 'getting' should be done 'well'. The phrases "get ready", "get back", "get down", etc. all use adjectives, too.