Add breaker for box for level 2 charger

Great Falls VA

Description

I am adding a level 2 car charger to my garage. 10-3 (ground, white, red & black) cable had already be run from box to garage, but nothing is connected. Issue is my breaker box is full, so need to: Add 2 Tandem 120V breaker to make space needed Add a Double pole circuit breaker for 10-3 cable Current breakers are Siemens brand