These are standard grammar topics which are explained in grammar websites and grammar books. You can use this forum better if you tell us what you understand and/or write your own examples. Then we can understand your specific problems and give you more useful feedback.

Thank you Matt.

You should use "difference" (noun) instead of "different" (adjective). There are many similar cases, such as: absence/absent, convenience/convenient, evidence/evident, innocence/innocent, patience/patient, silence/silent, violence/violent.