Disconnect Supply Line and Remove Old Valve

What happens here

After ensuring the water supply is off and the lines are drained, disconnect the supply line from the bottom of the toilet tank by hand, or using a suitable wrench if needed, to release any remaining water and air pressure. Next, using an adjustable jaw wrench, carefully loosen the old angle valve from the supply hose. Then, use a specialized Rigid one-stop wrench or a pair of adjustable jaw wrenches to unscrew and remove the entire old angle stop valve from the copper pipe stub extending from the wall. Be prepared with a sponge to catch any residual drips during this process.

Goal: Disconnect the existing supply line from the appliance and then carefully remove the old angle stop valve from the wall's copper pipe stub-out.