are you able to get into the windows 10 desktop ?
you can revert back to win 7 easily if the windows 10 is working. otherwise its harder
if you can get to the desktop in win 10
right click on the start menu
select update and security
select go back to windows 7
if you have already done a repair on the win 10 it will not let you go back to windows 7.
if you have not it should be an option
this post has screen shots and instructions of how to get there.
if it is no longer an option for you than you dont have a lot of options. You can try getting the win 10 working for you. or you can back everything up and do a factory reset to the original condition the computer was in with windows 7 but none of your personal stuff. then you would have to restore that stuff from a backup that you will have to make before you do the recovery.