"alt/option" not pulling Recovery Disk

While trying out different methods of triple booting my MacBook Pro I entered some commands into terminal. Now I am missing the recovery disk when I hold "alt/option" and and a GRUB menu pops up when loading linux that I don't remember from previous times doing this. I installed gdisk and ran command "sudo gdisk /dev/disk0". Any suggestions for me to go back and start from scratch? Thanks for any help.