1. If I do not care for sechar and am not scared of onesh why should I keep mitzvos?
Because doing right and wrong isn’t always about a reward. Things that are right are right because they are right and not because of the reward we may get. We should strive to do right for it’s own sake and not for the sake of the reward.
When you say “thank you” to someone for something they did for you, do you do it only because you see some reward in it for you at a later date? When you give up your seat on the subway/bus to another person who really needs it, would you really not do it and be completely selfish if there was nothing in it for you?
2. Why do we learn torah?
To learn what *is* right and what *is* wrong.
The Wolf