I wamt to start by saying I am in no way a professional welder.
My go to machine is a craftsman (Lincoln)110v mig. Looks to me like you need to increase the voltage and maybe even slow the wire speed. Doing so will help the weld "penetrate better, and not just puddle up on the surface. Get some pieces of various scrap steel and practice on a bench. Welding at odd angles and inder vehicles is not the best way to learn. Too many other factors make it difficult.
Practice is key.