Ipad wont turn on after glitching for several days !!!!!! i am utterly bewildered

Ive had my ipad for almost 4 years at this point, with no problems other than the battery being quick to die while uncharged and the mysterious problem of never having enough storage even after ive deleted all but 7 apps (yes, including the app store and 'settings'). But about two days ago, in the middle of the night, i watched half-conscious while my ipad repeatedly turned on and off, restarting and restarting with absolutely no input from me. I got sick of it and flipped it over to limit the light, but in the morning it was no better !!!!!!! I googled solutions, and they recommended that I update my Ipad. Well, okay, i guess i can do that- so i tried to update and (of course, i had to delete literally everything save the applications that literally made the ipad function first) what do you know, it flashed purple and black and restarted again !!!!!!!!!! So alas I bang my head on my desk and force restart my Ipad multiple times, check everything that i can, and attempt to update again. This repeats several times, each time the update somehow getting longer in wait time, and every single time it never finishes the update either because the Ipad simply doesnt feel like it or because it RESTARTS AGAIN !!!!!!!!!!!!!!!!!!!!!!!!!! And so i give up, go about my day, and the next day (yesterday) I attempt again to use my **** Ipad. Ive given up on actually updating it at this point, and while attempting to boot up an app it..... restarts! I sigh dramatically and head-onto-desk-bang a bit more, and unplug the Ipad, seeing that some people have reported problems specifically happening while charging. This time fares maybe slightly better, but if there was an actual difference it isnt significant enough to improve my problem. Every time I attempt to use an app, it restarts maybe only a third of the time, but i am constantly receiving 'server connection issue' warnings from whatever program im using when i know for sure that my wifi is good (it comes straight from a phone hotspot). At some point whenever it restarts it flashes strange green and multicoloured glitched colours at me, and im like okay yeah that cant be good! So i put down my Ipad, leave it to charge for the night, and go to sleep. Cue to this morning. Maybe an hour ago. My ipad just straight up wont turn on anymore ?!?!??!!?? Like, I get no warning, I get no vibration, It doesnt show the apple logo or any glitched variation thereof, its just a cold black screen no matter what i do. (It may be notable aswell that the day before, there seemed to be a severe buffer time between the Ipad registering the charging cable being connected and reconnected, which seemed linked to the processing time for everything else that Old Man iOS seemed to be struggling through.)

I literally dont know what to do anymore !!!!!! Much of my career is dependant on the files stored on the Ipad, so i cant afford to factory reset it without knowing for sure that i have a backup.

PLEAESEEE EHEHEEEELLLLPPPPPPP