With Macs, you have to pray and act fast.
Repairing is not an option, the battery is under the trackpad. The board is designed to be “one piece” so the newer your MacBook, the higher the risk of data loss
Once a short occurs, its matter of time before it slowly does out.
If you move fast enough you can probably connect an HDMI, External Mouse and keyboard and backup to drive immediately (Repair shops and Apple will try to charge more than $500)
Plug into an external monitor or TV while its still alive, and backup your data, or just to suffice temporarily.. MacBooks are friendly with most monitors. External keyboard and mouse will save the other headace you would have from using a partially functioning laptop.
Before you cash out on a repair, consider a newer MacBook, just do research on specifics like GPU’s, Thermal reliability, SSD lifespan, overall reliability etc
Either way, hold on to your MacBook, they are becoming collectors items.