No, you do not.
If you think you could want a relationship with him invite him on a date and see where it goes you dont need to love him now and you sure as hell shouldn't say you do yet
If only u love him like that.
just say thanks
No. You can tell him you care about him if you feel the need to say something, but it's best not to lie about that sort of thing.
No. You can be gentle, and tell him you're flattered but don't feel the same way. Lying and saying you love him in return wouldn't be fair to either of you.
Just be honest so that he knows where he stands with you.