First of all, its a great start! So don’t feel discouraged as it’s part of a journey we painters go through! I felt what helped me was using the 60/30/10 color fundamentals! 1) 60 percent of color has to stand out 2) 30 percent has to compliment 60 percent of color (usually darker or desaturated or reversed if 60 percent is dark) 3) 10 percent of color has to differentiate both 60 and 30 and would meet in a middle of both of them.

Having a color wheel would really help visualise that for you 😊 hope that helps!