Hi, Kayla. Welcome to the forum, glad you joined!
Where are you? This is one of the many things that knowing your area could help. If you are in Australia it doesn't do a lot of good to recommend something specific to the US. If you modify your profile to show your location like many of us have that information will always be available.
Debbie's article is great. Lots of good ideas.
If you are in the US you might call your county extension office and chat with them. They may know something that could help you. They are generally involved with 4-H and are often involved with people that keep chickens. You never know when you might strike gold.
I understand you want the boys to live but sometimes that is really hard. You might call a local zoo, animal rescue, or sanctuary to see if they need young roosters to feed their animals. At least they would be going to a good purpose.
You ask how many is too many. What are your goals for having chickens? Why do you want any roosters? The only reason you need a rooster at all is if you want fertile eggs. Anything else is personal preference. Nothing wrong with personal preferences (I have a few myself) but those are wants, not needs. Lots of people on this forum have all-girl flocks and are very happy. Others would not have a flock without a rooster, even if they never hatch an egg. It is your goals, wants, and desires that count for your flock, not mine or any else's.
Once you decide how many you have to look at how. They are living animals, no two are going to behave identically. Some people can keep multiple roosters together without incident but often there can be fighting and violence. They are going to know which one is boss. Sometimes that is determined by intimidation. Usually it involves fighting. That can be a fight to the death or one may decide it really isn't smart to keep fighting and run away. They may reach an accommodation on how to live together instead of one dying.
How much room you have is important. If one decides to run, he needs enough room to get away and probably stay away. Sometimes different roosters claim different territory and they each have their own harem. The girls decide which rooster they want to be with, by the way. Sometimes the boys can live together.
Sometimes you can make a bachelor pad. House the boys together separated from the girls. If there are no girls to fight over they often don't fight.
My general recommendation is to keep as few boys as you can and still meet your goals. For most of us that is probably zero or one boy though many of us have multiples.
Good luck with it. Giving up those boys can be really hard for some people.