Tandy is dropped off by Liam and then sneaks across the street into the empty church she calls home in episode 1x01 "First Light". Tandy tries to summon her light dagger again and then packs up all the stuff she stole from the guy she stabbed in episode 1x02 "Suicide Sprints". Tyrone has a vision of young Tandy handing out roofies to a line of people as if they were taking communion in episode 1x03 "Stained Glass". Appears in 7 more episodes.
Source: MCU Location Scout