The caliper sliding pins may have seized up causing the pads to remain in contact with the disc , or the handbrake shoes are in contact with the drum. Incorrect adjustment or seized cables may be the issue.
To investigate further the wheel must be removed and the braking system examined.
A less common fault is failure of the wheel bearing.
All the small parts, caliper pins, return springs for the shoes, handbrake cables are inexpensive from a motorfactor and complete reconditioned calipers and disc/drum from a brake parts supplier not too expensive.