I have a lot of muscles due to going to the gym multiple times a week. People get surprised when they hear that I'm 100kg, it doesn't look like it until I take my shirt off.
If you want to gain muscles, my advice is to just be consistent with your work outs. Find a schedule that you like and don't deviate from it. Just as an example I'll provide you with mine:
Tuesday: back/stomach (morning) + HIIT cardio (evening)
Saturday: long cardio workout (10-20km running)
Sunday: optional cardio, in winter time I went to the gym watching skiing competitions on the crosstrainer for 1-2h.