You have to have a rooster for your hens to lay fertile eggs. That is the only reason you have to have a rooster. Everything else is personal choice.
As said, you can eat fertile eggs.
A rooster has nothing to do with a hen going broody or a broody hen hatching eggs. Whether a rooster is present or not, if a hen goes broody you can give her fertile eggs and she will hatch them. Some hens will go broody whether a rooster is present or not. Some hens will never go broody, whether a rooster is present or not.
If you have a hen go broody, you should be able to get fertile eggs without a whole lot of problems. Go on your state thread on this forum and post there. Someone pretty close to you probably has fertile eggs they can provide. Or talk to the people at the feed store. There is a pretty good chance someone there has fertile eggs or knows someone who does. Or call your county extension service, in the phone book under county government, and talk to them. Or look on Craigslist for your area. If you really want them, finding fertile eggs is not usually a problem. If you want a specific breed of chicken it might be a little harder, but them it might not.
Your problem is much more likely to be that a lot of hens don't ever go broody. You may get lucky and you may not.