Bob always talks about using Odorless Paint Thinner, so you’ll need some. Be sure to get a high quality orderless thinner or you will stink up your house or studio. With a true odorless thinner you can walk into a studio with 20 painters and barely smell anything. The Bob Ross brand thinner is excellent, as are a few of the better brands. If you pick up something like "Orderless Mineral Spirits" from a place like Home Depot, you will definitely have a strong smell — in spite of the name.
To clean your brushes the Bob Ross company makes a nice cleaning bucket with a screen in the bottom. https://www.dickblick.com/products/bob-ross-brush-cleaning-bucket-screen/
And since you probably won’t be “beating the devil” out of your brushes on your easel, like Bob did on the show, there is a Beater Rack that fits in a trash bucket. It works really well. https://www.dickblick.com/items/bob-ross-beater-rack-5-14-x-5-34-x-10-34/