Doing some easy grooming sessions several times a day and ending with a treat will get you to where you want to go. They must learn to associate grooming with something pleasant and not as a punishment. Patience, consistency, and lots of praise and encouragement are necessities. Keep the session short at first. Trying to repair days worth of tangles all at once is only going to cause frustration for everyone.
Find a good conditioning spray to use on places where it is hard to get the comb through. If your pup has already developed a bad mat it is better to cut it out than cause the baby pain.
A dog will not struggle to get away from an activity that they have learned to enjoy. It takes consistency and the best time to start is the day you bring your puppy home.
If you have to do this on your own you might try holding the pup on your lap. That way if he does get away he won't get injured.
This little grooming table is also helpful for those who don't have 4 hands:
https://www.petedge.com/zpetedgemain...c-locale=en_US
It is also available on Amazon and a few other pet supply stores. I think Pet Edge has about the best price though. You can put it on the floor or any table. If you are going to do your own grooming later on it is really helpful for doing the body work.