light strip attached to Motor home below awning?

You can use double sided tape.
Just make sure the lights are rated for out door use.

i believe AMAZON has a 16 foot strip of LED lights that are waterproof. They make an very nice looking patio.

Be careful of cheap LED light strips. I used one and it failed in a year.

On my current TT I found a strip that came in a silicone sq. tube. It seems to be holding up nicely.

I also used a double sided tape to attach, but used a "butyl" tape from Home Depot, it's a little expensive but it is holding great! I also suggest to add a plastic cable strap that us screwed in at rfw ends, so wind and weather won't start to peel it up.

I got a strip off Amazon for a good price but the tape doesn’t last long. I got some 3M double sided automotive tape which has held for 2 years with no sign of letting go. I attached mine to the underside of the awning track that is attached to trailer and wired it into the porch light.

Weatherproof LED lights is what I'd use. I have LED's but they are not weatherproof (I coudl put 'em in a vinyl tube) Get peal and stick so you don't need to if you will pardon the pun.. Screw Around.

You and get led strip covers:
cover

I use these at my home. They're 12 volt:
Lights

You can buy 5M waterproof peal and stick LED strips for $7 that you can cut to the length you need if 16' is too long. I agree chips stop working to soon when hooked to the RVs fluctuating 12V power. For $12 you can buy ones with a 120V to 12V converter that will help the longevity but you would have to run an inverter or be hooked to shore power. For $7 just replace every couple years if part of it stops working. I've found the 5050 size chips last longer.

We installed this one just as you’re asking. Works great. RecPro RV Camper Motorhome Travel Trailer 12' WHITE LED Awning Party Light w/Mounting Channel & White PCB 12v Light https://www.amazon.com/dp/B00UK40SSU/ref=cm_sw_r_cp_tai_wwiBAb8YMQ7PH

We have the RecPro lights as well. In addition to using the tape, I put a dab of silicon at each end.
Wiring them proved to be a little challenging as I didn't want any wires showing on the outside. I ran the wires from the end of the tube through the wall just above where the awning motor wires come though. From there, ran them behind the cabinets following the awning wires. And then installed a separate switch next the the existing porch light switch.

Gary

On our previous HR coach...there was a strip of lights we found at our local camping supplies dealer and it went on with special weather tape..it was 12v and we had to wire it into the 12v going to our refrigerator...had a remote you could change the colors on it too.