Chicken gumbo? Interesting, do you make it hot or have ways to soften the heat? My family loves heat but I can't do it so I discovered tasty Poblano peppers these days and the family adds something from the Hot Ones show to their liking. If you are of the mind to share how to I would be of the mind to try it
Gumbo in and of itself is not inherently spicy; it only gets that way from what you add to it, which is something you can always do at table.
Chicken gumbo typically contains no tomato products, while seafood gumbos usually do. It also typically does contain sausage rounds or ham bits, and the Holy Trinity of veggies: onion, celery and bell pepper. You can save time and money by buying those veggies pre-chopped and frozen, often bagged as mirepoix.)
Basically, to make gumbo, you make a roux first; there are many ways to do this, including no-oil variations where the flour is browned by baking; Google and
Youtube will explain all. Poultry gumbo uses a medium-dark roux; often described as chocolate-colored. Once your roux is made, put it in a large stockpot and add stock or water (stock gets you a much better flavor) Add the finely chopped trinity and some garlic, and then add the chopped meats of your choice. It should cook on low heat for at least an hour, and several hours at simmer tends to be better. The chicken should be dark meat; it is less likely to go to shreds during cooking. The most common type of sausage used in poultry gumbo is Andouille, but really, any type of sturdy sausage will do if you want it. (Creativity is the whole point of gumbo; it's meant to contain whatever you want to put in it, generally speaking. However, certain veggies with a tendency to disintegrate when cooked slow should not be used; no carrots or potatoes, for instance. You want veggies that will stand up to being simmered for a long time.)
Contrary to what supermarket "gumbo mix" packets would make you think, rice is normally never cooked *in* the gumbo, because that makes the rice too mushy and overthickens the gumbo. Rice is made in a separate pot as usual, served into the bowls, and the gumbo is ladled over it and mixed up at table. Gumbo (without rice in it) freezes very well, and is one of those dishes that works almost better when re-heated.
BTW, with regard to rice, I've made it the same way nearly every day for over 50 years. Heavy saucepan with a tight lid, 1 part raw rice to 2 parts water, plus a shake of salt and 1/2 tsp of oil. You put everything in the pan cold, stir, cover tightly, set the pot to simmer for 20 minutes. Rice that has been par-boiled or pre-cooked should be cooked according to package directions, but IME, the above technique works just about perfectly for any type of raw rice.