Hi,
Is this an Intel or a Apple Silicon mac? Using Apple Diagnostics mode might help.
If it is an Intel mac, hold D on startup until a screen shows, and hit Start. (If that doesn't work, try Option-D.)
After a while, a screen will show, telling you if there's anything wrong with your hardware. There will also be reference codes, described in this article:
Apple Diagnostics reference codes - Apple Support
If that comes up with no errors, try resetting your NVRAM/PRAM by holding Command-Option-P-R during startup, and your mac will appear to restart. Keep holding these keys for about 20 seconds. Then boot into Internet Recovery.
If that doesn't work, I'd recommend taking it into an Apple store.