How do I get an instructional manual for the awning on my RV?

You're taking the awning in you're retracting. It if you flip that and you go take a screw run to forward you're actually extending it. And that's it for how to manually override your awning.

Not sure what you mean by "middle arm" and are you referring to the patio awning? What is your RV?

The motor or a relay may be the issue here.

Loosen holding screws and unclip both arms
Flick the up/down lever then pull on black cord as you walk back away from RV
Slide both side arms up main arms, lock in place and then tension the awning and tighten lock screws
Release lock clips on main arms and slide them up [ halfway each side is probably best for your awning]
Support legs can be left attached to RV [safest] or can be separated and stand upright, using tent pegs into ground to secure or awning tie downs

That's an interesting question as for me because every single year the market shows us new manufacturers which are even better then the previous ones. For example the latest source
https://highskyrvparts.com/rv-parts/awning-shade/room-enclosures which I checked while looking for rv awning enclosure. It also may be helpful for you (if you're still interested in).

Teresa, I will post links to videos on awning set up and use. Check the attached links,instruction and guides, Good luck
"I hope this helped you out, if so let me know by pressing the helpful button. Check out some of my other posts if you need more tips and info."
How to Use the Awning on Your RV
RV Awning Tutorial
1 How to Open RV Awning
How to Use and Maintain Camper Awning Pete RV Service Tips

Manual or electric. If electric press the switch located inside the unit. If manual, you will need to go to each arm and press the release clips to unlock the arms (usually black but may be a lift up lock). Next tank the long rod with a loop on one end and a 90 deg hook on the other. Toward the front of the coach at the top of the awning you will see a small lever on the awning. Use the loop end of the rod to pull the lever down. Take the other end of the rod and insert it into the black strap that should be barely hanging down and pull down as you back away. This should pull the awning out. Once pulled out all the way, go to each end of the awning. Close to the wall of the RV there should be an arm hanging down with a knob on the back of it. Grab the bottom of the arm and slide it out and clip it into the end of the extended awning arm. Push down on the lower arm to tighten the fabric and then tighten the knob. Once both ends have been tightened then on the lower arm there will be a pull out handle in the middle, pull it out to release the lock pin and lift the outer portion of the lower arm up to raise the awning to the desired height. Repeat for the other end. If it is raining or windy put the awning away. DO NOT LEAVE IT OUT! The wind will catch it like a kite and rip it off of your trailer. Rain will fill it up like a swimming pool and collapse the center tube and trap you inside of the RV.

Check out for the brushes in the motor. They might be worn down and need replacing.