Macbook shuts down after typing in password

So. I was watching a vid in youtube when my computer suddenly stopped responding and just powered of. 2hrs later I felt bored and opened my macbook pro, and I typed in my password, but then that problem came in. So now I searched google for a solution and I tried two solutions. First one is press shift for a long time during the booting. It brought me to a language chooser and it was about reseting my password. Clearly the problem isnt about the password. And then so I tried the command+R solution and it brought me to this platform after the grey globe. And I tried the repair thing for my MacIntosh and my other MacOs thingy. After that I restarted it and still it was the same problem. So I did it again, command+R.

After that I went to my MacIntosh HD drive and It was full ~250GB/250GB and 0 available 0 unper...(whatever) so I ERASED EVERYTHING IN IT. And was left with 0GB in my MacIntosh. So I restarted my laptop and this question mark file appeared. And I did the, command+r again, and I went to choose a starting file, but nothing appeared, and I went to disk utilities, my MacIntosh was 0GB, and it was named "untitled", but after I did the Recover MacOS option, the file name became "--", Now I dont know what to do, I might have lost everything even the predoenloaded apps in my macbook pro😭😭 Is this something very serious?! Is there anything I could do manually? It doesnt matter whether I lost my files and stuff because nothings really important in 'em, but Im worried about my laptop's predownloaded contents and programmes😒 Just because of that silly problem. I really really hope you could help mr ASAP. Im from Singapore, and would do anything

Theres no start up disk because of that

I really really need help asap