Hi Babit,

1. the difference between 'étudiant' and 'élève' isn't easy to explain but you might appreciate the following link which tries to do this very thing:

https://french.stackexchange.com/questions/21980/what-is-the-difference-between-%C3%A9tudiant-and-%C3%A9l%C3%A8ve

2. Too many tenses to list, I would suggest you let Kwizbot take you through the selection in a logical way.

Bonne Continuation!