That certainly looks like a bad prolapse. In needs to be kept CLEAN!!! and moist.
A vet is your best option.
If the vet is out of reach for what ever reason (cost, distance, closure...) this MAY work, i have never done this nor seen one in person, so I have no experience with such things. I can't say if it will work or cause harm.
https://www.youtube.com/watch?v=pLn4CmlZK6U
The idea is solid.