The first thing you might want to do is figure out your hair's porosity. Take a strand of your hair and place it in a bowl of water. If it floats for a very long time, your hair most likely has low porosity - it resists water from entering the strand. If it floats for a long time and begins to lower in the water a little, your hair probably has normal porosity - it does not resist water as much. If your hair sinks, it has high porosity - it lets in water very easily, but also loses water just as easily. Another test is to run your finger down the strand of your hair. If it slips down very easily, then your hair has low porosity; slides down the strand moderately, normal porosity; does not slide too easily and catches on itself, high porosity.
Protein is used to strengthen weak spots in the hair strand. Figure out if your hair is very porous, because if it is, you may want to look for protein treatments. These are typically done every 4-6 weeks. Thickness and coarseness don't necessarily determine your hair's need for protein. For example, I am a thick coarse curly with normal porosity, so I find that protein isn't too necessary, although my hair doesn't mind it. Too much use of protein in the hair can cause it to be brittle, hard, and easily broken.
Like curlyhaley said, the best moisturizer is water. I use a mixture of water and Califia Moisturizing Spray from Komaza
. You can seal in the water or moisturizer with an oil like olive oil or coconut oil, or, since I'm assuming your hair is thick and coarse, a butter like shea butter or cocoa butter is a good sealant that shouldn't weigh down your hair too much. Mixing butters with oils (olive, coconut, almond) makes them easier to apply to the hair. Hope that helped!