Need help in installing Ventura

Hello, so I’ve been following a tutorial on youtube on installing macOS Ventura on a Mid2014 macbook pro. I followed every instruction on the video, but when I try to install the OS this message pops out, which translates to “An error occured during the preparation to the installation. Try to launch this application again”. So I tried, but nothing changed, same error. How do I fix this? Is there a way to go back to Big Sur?