Can't attach file because it crashes so fast.

I downloaded the newest beta because of hype, right? Everything was meant to go right, right? Did it? No.

I booted up Bedrock when it finishes, it loads up the beta startup bar 3/4 of the way, then crashes. This isn't a one time thing. I've booted up the beta multiple times just to get the same answer of a crash 3/4 of the way booted in.

Any help? If I have to uninstall, please insert a guide for me to back up my worlds.