Dont make it too complicated if you're beginner/intermediate, 1000 people will tell you 1000 things and 900 of those would be bro-science.
goto bodybuilding.com forums (not the articles, click bait for supplements etc), read the stickies in the sub forums that interest you. You dont really even need supplements at the very start and at end of the day, they're mostly for convenience unless you're aiming for some championship etc.
Hardest and most important part is the food. Right kind and right quantity with the usual excercise fundamentals oriented to whatever your goal is, strength or muscle growth or endurance etc.
Dont get injured, it's PITA, one of my left has had knee injuries, foot injuries and recently a fracture, I got injured because I did'nt give a fuck about previous injuries which led to poor recovery and the leg getting relatively weaker than the other and the load balancing did'nt work out. So if you get injured, take it very seriously, especially it's the joints etc.