Hello I am trying to boot a linux media (I tried

Question

Hello I am trying to boot a linux media (I tried

some different distros) and when I want to boot the system from usb I stuck in grub commamd prompt.
I only have windows but my old removed systems' grub settings (two fedora installation and one ubuntu) still remains.
I tried a lot of ways in the internet to repair it and boot a new linux, but no one worked for me.
Can anyone please help me and tell me what to do step-by-step?
I think the problem is old grub config.