Hire a pro to replace the roof.
Last spring a raccoon tried to make a nest in our roof. She didn't get through the sheathing, but she did tear out a lot of rotten shingles.
The owner wanted to save money, so they did it themselves. 4 adults (landlord, landlady, their daughter, her boyfriend), a little scaffolding, a nail gun, a chop saw, and many stacks of cedar shingles.
They would strip the shingles off a section, and fix sheathing, add tar paper or whatever, then reshingle. At night they covered exposed areas with tarps.
It took them much longer than they planned. Soon the weather turned stormy. The wind tore off the tarps and the rain came in the attic. One morning we woke up to a drooping ceiling, dripping steadily. It missed my wife's wedding dress by a few inches.
Now they had a new set of problems: standing water to remove from the attic, ruined roof insulation, water damage to the ceiling.
Learning a lesson, they got diligent about securing the tarps at the end of the day. That meant more of their time and energy going to tarping that could have gone to roofing. Since they were much slower than pros, they spent more days on the job, so they did a lot of retarping. There were a few windstorms during that period, and in the evening they'd drive by to check on the tarps. (More time & energy.)
They trimmed the cedar shingles on a chop saw. They seemed to spend a lot of time passing shingles up, measuring them, passing them down, cutting them, and passing them up again. I think pros use a roofing hatchet to do this quickly, but they didn't have that skill.
The roof on this house is complex, due to two additions over the years. They spent a lot of time on the valleys.
At one point the young couple had an argument and he fell off the roof. He was OK, but scared. That slowed the work down even more.
It took a total of 6 weeks. I would guess that a team of pros could have done it in 4 days. That would have meant a lot less time applying tarps and cleaning up water.
There was also a big mess, including hundreds of nails in the grassy yard. We still don't walk around barefoot.
If you have never replaced a roof, hire a pro. (If you had more time, I'd say get on a crew and do a few roofs under the eye of an expert, before doing your own.)