sumerainWall Mount Tub Faucet Bathroom Taps, Polished Brass with Waterfall Tub Spout and Rough in Valve, High Flow

Does this have a lever that lets you change from tub faucet to shower?

Does this work with a shower head as well? As in, is there a lever or switch to stop the water from coming out of the faucet and diverting it to a s?

I have a wall mount valve by Delta, will your fixtures work with this valve?

Very heavy. Does everyone mount this using only the single brass nipple? It does not look like it could possibly hold up.