I was dual-booting Windows 10 and Ubuntu on my laptop for some time. A while back, my laptop died and had to be sent in for repair. Turns out there was some bug in the BIOS so that it had to be reinstalled. My SSD is untouched, though. It has not been wiped, and Windows has not been reinstalled.
The only problem is that I no longer get the purple boot screen where I can pick what OS to start. It just goes straight to Windows. My Ubuntu installation is probably still there, or at least my Windows partition is still smaller than the complete drive.
What do I need to do to be able to boot Linux again? My skill level is very low here, no idea how bootloaders or anything like that works.