Charging question

Depends on iPad model and its supplied Apple power/charging adapter block and how much battery power is remaining.

Using an Apple 10W power/charging adapter will tale an iPad up to 6 hours, or so, to fully charge.

Using an Apple 12W power/charging adapter will tale an iPad up to 5 hours, or so, to fully charge.

Using an Apple USB-C 18W or 29W power/charging adapter, with using USB-C to USB-C cable or USB-C to Lightning connector cable, will tale an iPad between 2-3 hours, or so, to fully charge.

It depends on how far down it is. Are you using a 10W, 12W or 18W charger? A few hours to several hours

Charge and monitor the iPad battery - Apple Support