Boot issue: Minimal Bash-like editing is supported

Hello,

I deleted a primary partition via Windows and now my PC only boots to a black screen with "GNU GRUB version 2.02
Minimal BASH-like line editing is supported. For the first word, TAB lists possible command completions. Anywhere else, TAB lists possible device or file completions"

I have a dual boot of Ubuntu / Windows 10.
I cannot boot anything else because this is the first thing that appears on the screen.

My PC is therefore unusable for the moment. I don't know how to boot from the live Ubuntu CD since I can't change the boot options via the BIOS (at least I haven't succeeded...).

Could someone help me out of this?
Thank you!

Deadman

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