my hp laserjet pro m234dwe won't pick up paper at all, just makes a grinding noise. what do i do?

The pickup roller is likely dirty or worn. You need to clean it.

1. Turn off the printer and unplug the power cord from the back.
2. Remove all paper from the input tray.
3. Flip the printer on its side.
4. Release the blue latch and remove the panel.
5. Dampen a soft, lint-free cloth with alcohol or water and wipe each roller. Apply moderate pressure.
6. Wait 10 minutes for the roller to dry completely.
7. Reinstall the panel, flip the printer upright, reload paper, and plug it back in.

If that didn't work, check the paper itself. It must be good quality, free of cuts, dust, and staples, and designed for laser printers. Don't use inkjet paper or paper with glitter.

Heads up: Always use paper that meets HP specifications. Rough or damaged paper is a common cause of feed problems.