Hello, I’m thinking about taking in two more 3wk-1month old peafowls but I already have two 3 month old peafowls. Would it be okay to keep them together or would I have to keep them in separate spaces?
The only way to find out is to put them together and see how they act. Put a couple of hiding places in the pen and have a plan B in case they don't get along.
It's good practice to always quarantine new birds. Here is an article about it. It's written with chickens in mind but the same principles apply to any birds.
After quarantining I would put them adjacent to each other so they can see each other and get used to each other before finally merging them.
I would merge them under supervision at first and, as KsKingBee said, make sure they have plenty of hiding places. If it doesn't go well, you can separate them back into their adjacent areas and then try merging again in small supervised sessions and work up to longer periods in a gradual way before a permanent merge.
A choice of multiple feeding stations, waterers and roosting areas distributed around the aviary are always a good idea when you have more than a couple of birds together.
Also, you could look up creep feeders. It's basically a feeder or feeding area that only the smaller birds can get into so they can eat without the bigger ones hassling them. You could apply the same principle by making a whole "safe" area that only the little ones can get into.