Even a small hen can easily raise 7 chicks. I think you could leave her with 10 or 12 eggs and put the rest in the incubator.
Incubator timing in this case is tricky because you want to coordinate your setting with your broody hen. Do you want the broody hen to raise incubator chicks, or would you rather raise them yourself and have them “imprint” on you? (and be friendly to you) ?
Just note than hen-raised chicks are a little more skittish and aloof of people. They are also more independent and confident of taking care of their own needs. No electric bill!
Brooder-raised chicks will likely imprint on you. It’s the cutest thing to have them follow you for feed when they’re bigger. They often imprint on only the person who raised them and will ignore other people.
If you have an incubator and a starting-out broody hen, you can decide whether you want the hen to raise most of the chicks. This is certainly easiest, but may not yield the most friendly chickens.
Giving the hen a day or two to hatch the babies, after that it only requires putting mom and babies in a cage with chick starter and water. Some people just let mom and babies run free, but that requires a clean and dry run. It might work in the US Southwest or other dry places.
In a “maternity cage,” you just need to feed and water mom and the babies. This is very easy, but the chicks will imprint on their mother and think “chicken” rather than “a human is raising me.”
Or do you want to run the brooder while spending time, electricity, and effort to raise them yourself in order to get some human-friendlies?
This requires taking care of the water (so the babies don’t drown) with marbles, feeding them, keeping them warm, and cleaning or changing the bedding. It’s OK if you are at home most of the time, which is common right now. It’s more work, but the result will be fun and mostly friendly chickens. (Disclaimer: bad rooster genetics are always possible).
It’s your choice and based on your goals for your flock.
well there’s a chance they all won’t make it? We had a hen disappear once and just when we lost hope she came back with 12 chicks!!! She was great mom and they all did great! Not sure how 20 would be. I think it depends on if you want them or how far along they are. There’s probably a way to make it work if you really want too. The main concern would be if they could all stay warm. I’m not sure they would all fit under her but there are heat lamps and hanging plates you could put next her her if you really want. Best of luck!!!
