grub.cfg is actually in /boot/grub/ as in screenshot.
/home/swarfendor437/Pictures/edit grub.cfg.jpg
Edit line 201 at end - it is in read only mode so you would need to open a terminal and enter:
cd ..
cd ..
cd boot
cd grub
sudo chown [your username] grub.cfg
then whilst still in terminal:
sudo nano grub.cfg
and edit the line around 201 that starts vmlinuz - it might wrap round to next physical line - add 'nomodeset' at the end then Crtl+ O to write changes - save as grub.cfg and tell it to overwrite existing file, then Ctrl+ X to exit out of nano.
