Found out what happend, the reason it wasnt booting is beacouse i deleted everything in the roms (usb).

Alright, so im new here and i just installed RecalBox on my Raspberry PI 3B+.

I connected my usb to get some games from this github reposistory and after rebooting the recalbox trough the Recalbox Manager (trough the ip address) i was met with my raspberry staying red, no matter how many times i rebooted it was stuck at the same red light, so i stopped the fan and then powered it on, i confirmed that the sd card wasnt booting.

After putting PINN back on it now its booting.
Can anyone explain what happend?
Also with it can someone explain how to put the roms from the gihtub reposistory above onto my recalbox?

Thanks
T420User