Deleted an admin account but files still on hard drive...

Hello!

I recently upgraded MacBooks and used migration assistant to make the move pretty easy. I am giving my old MacBook to a family member, so I created a new admin account, logged in to the new account, and then delted my admin account. The process took more than 12 hours and when I woke up this morning it still said it was deleting my account. I read online that some people restarted their computer and when they did, the user account was gone. I tried this and while my user account is gone, if I look at the storage there is only 29 GB free and the rest is used up with pictures, music, etc. (according to the storage bar). What can I do to fix this? I want my files gone, but some of the programs I want her to have. I don't know how to access the portion of the hard drive that contains my old files since my user account is no longer listed. Any and all help is GREATLY appreciated. THANKS!

James