Reincarnate With RPG System

I am re-working this novel. Synopsis: A soldier who died because of a god's mistake are being reincarnated to the future but the earth he reincarnated is no longer the same. He ask a compensation to the god to grant his 7 wishes but the god decided to give him a system instead. What will he do in his new life with his system? NOTE: The 'system' in here wont have a consciousness so don't worry that MC will be slave to the 'system. It will just have a basic function and it will have a quest but its just a bounty type quest so he can freely accept or reject it.