The main house shutoff may not seal.
If that's the case, it will continue to drip.
The toilet shutoff can be replaced if it drips.
If it's copper from the wall, a sleeve puller may be needed to remove the back nut.
If you just want to stop the water and don't want to involve yourself with replacing the stop, pick up a lav suppy with a 1/2" end and thread a 1/2" boiler valve on. That works in a temp sitiuation like this.