If I cant remember my restrictions passcode on my iPod touch, what should I do

on 6th generation and earlier iPods you have to completely erase the contents of the iPod. See: If you forgot the passcode on your iPod touch, or your iPod touch is disabled - https://support.apple.com/en-us/HT211080. However, you can't restore the contents from a backup as described in the article because it will restore the restrictions code. You can, however redownload all your music and all the apps if they are still available for your iOS version.