Blue screen ender 5

I just bought my ender 5, so I'm fairly new to all of this. But here are the steps that I followed when I got my printer: 1) I configured my arduino to be a programmer2) I flashed the bootloader3) I flashed marlin 2.0 with VSCODE. The latest version gave an error, but it looked like the devs made a mistake by adding the same file twice. I got rid of the redundant files and managed to upload a working marlin environnement. However I still needed to configure it for my BLTOUCH. So I followed the guide from this video to do so: https://www.youtube.com/watch?v=Cp3D_1vJpvMSuddenly but I got a blue screen after uploading my code. Since then I never got it working again. It flashes 3 times when I boot it up (whilst the BLTOUCH is booting as well). The BLTOUCH is blinking red (since it probably couldn't self test). I flashed the bootloader again,since that looked like a reset to me. Then I tried to see if it had something to do with my settings. So I uploaded marlin 1.9 with the ender 5 configs like this repo: https://github.com/3d-printing-canad...h-Installation .Sadly It's still a blue screen. I checked all the wiring, and everything seems like it's fine. If I try to upload new firmware, it always does so correctly. This is the output I get when I upload: https://pastebin.com/wenaAj9t .I have been searching for a solution online for almost 2 days now, and couldn't really find useful answers. So I hope that someone can help me here?