lose fat

Hello, I am posting Because I wish to run S4 andarine for 12 weeks because I want to put on lean muscle mass and lose some fat. Would I be able to run this by itself or is it required that I buy something else to run with it. I'm 25 years old 5 foot 9 in 160 lb

tell me more about these compounds called sarms that I am learning about, can you explain what they are to me in simple English I don't feel like reading an entire article or watching a 20-minute video about them. Like do they help us gain muscle and lose fat that's all I care about