Usually you want about 15 females to maybe 4 males (I think). @jamest0o0 is the Bug Lord of the forum and could help you find roaches your cham will eat and get you set up with starting a colony.
I use a big smooth sided or clear rubbermaid tote...either drill lots of tiny holes on the lid or cut out a section and attach screening to it for ventilation. I feed them the same that I gutload with...fresh greens, veggies and a little fruit. I also feed them all Bug Burger with added bee pollen and spirulina. Toss in some egg crate or toilet paper tubes for them to hide in. They reproduce best around 90*. I’m in Florida so I just keep them in my garage and don’t need to provide extra heat.