Dry-fit the pipe and PVC pipe connectors fitting ... especially if you can't thread on an adapter. Each coupling is labeled with all the different types and sizes of pipes it can join. Slide the pipe ...

These days, most drains are made with PVC or ABS plastic. Plastic drain fittings are usually glued, but the ones you might need to remove temporarily, like cleanout plugs, are threaded.

Join the EMT and the PVC conduit under the deck with a male adapter and a threaded coupling. Bring a second length of conduit up from the tee conduit body for a switch box, and install the switch box.