Hi @thiccislander ,
The fall may have loosened the cable connection from the display assembly on the systemboard. Worst case is that it internally damaged the display assembly or something in the screen’s backlight power circuit on the systemboard. The display assembly cannot be repaired. It has to be replaced
As a DIY repair all you can do is to open the phone and check the display flex cable connection on the systemboard is secure and if so, then is to temporarily replace the display assembly to prove whether the problem is in the display assembly or in the systemboard.
Here’s the ifixit Samsung Galaxy J1 / J100 Touch Screen & LCD Replacement guide which may help.
Replacement screens are available online. Just search for Galaxy J1 LCD screen to get results for suppliers.
If doing all this seems to daunting for you, contact a reputable, professional mobile phone repair service and ask for a quote to repair the phone.