SteamOs pc installation

Hi, u just flashed steam OS on my full AMD pc, it works pretty well until i click on "proceed" for rebooting th pc and finalizing the installation, i lost my video signal, and.. nothing happens next.

I used rufus for the bootable key

Here's my specs :

Ryzen 5 5600T

Rx 9070 16gb

500 gb NVME

I tried etcher too, it didn't want to flash the iso files at all