To replace the low oil level sender you will not need to do much more than loosen the engine mounts, lift the engine slightly, then place a 2x4 under the front edge of the upper (aluminum) part of the pan and the sub-frame. Lower engine so it rests on the 2x4 while you R&R the lower oil pan. Use a 5mm allen with a swivel (1/4 5mm swivel socket by Snap-on works best) to remove the forward section bolts, a regular allen will do the rest. Less than 3 hours on your back, under 2 hours on the rack…………..at a casual pace.
I apply a little “Ultra Black” sealant to the inner part of the sender, you’ll want to clean the block side with brake-kleen prior to installing the sender.

The lack of power can be a few different things, you will need to have the vehicle scanned for codes. Look for DTC’s in LH-SFI, DM, EA or ISC/CC, and DI. The engine harness may be a must, the actuator may also be a must just look at the insulation and it will reveal itself. This would be a good place to start before any of us could offer you meaningful suggestions.