To stop disc brakes from rubbing on a bicycle, you can follow these steps:
- Check the rotor for any signs of damage or warping.
- Loosen the caliper mounting bolts.
- Squeeze the brake lever to center the caliper, then retighten the bolts evenly.
- Check for even pad-to-rotor spacing.
- Repeat adjustments if necessary, ensuring proper clearance and alignment.
You can also look through the info here https://www.bikertricks.com/disc-brakes-rubbing/ I’m sure you will find some useful tips there.
But if you tried several ways and severe rubbing persists, it’s better to consult a bicycle mechanic for further assistance.