Broken MacBook boots grub I had installed a Ubuntu partition on my Mac, but last night the keyboard broke, so I was trying to reinstall Mac OS from the recovery mode and accidentally wrongly deleted all the partitions my Mac had and now when I turn on the Mac I get this screen

I know I messed up the computer, but is there any way to fix this? Like, deleting all the data and all partitions and reinstalling Mac OS.

I have thought of using any software like DBAN, to hardly erase all data on the drive but I don't know if I can still boot from a external USB drive with mac OS on it...
If you have multiple boots on your computer have you tried holding options when your computer is restarting? I use this to boot into different OSes.

Otherwise, you should be able to install MacOS by using internet recovery. I have replaced an SSD with no partitions on it and internet recovery helped install the OS fresh on the new disk. Here is an article that helps you get into internet recovery. TL;DR hold command-options-r while your computer is booting up.