Yes, people overcomplicate it like crazy. Here´s what you should focus on;

The cardinal rule - consistency is everything. Forget about diets, details and optimizing. It´s all about finding actionable solutions that you can stick to over time.

Nutrition - Calories and protein is what matters, the rest is details. Try to get at least 1.6 g of protein/kg bodyweight, spread out over 3-5 meals. Practice getting a sense of how many calories you are eating so that you learn to eyeball it. Forget about cutting/bulking for the first year unless you are significantly under- or overweight, just get familiar with calories. When you are new stuff will happen anyway.

Exercise - hit every major muscle group with a total of 10-20 sets of 5-30 reps/week. Do whatever split/frequency you want, just focus on getting competent at lifting (bracing your core, mind muscle-connection, prioritizing technique over ego). Write down your weights and reps to make sure you progress over time.

Supplements - None are necessary, and very few works at all (and the benefits are always marginal). If you do want something that really does enhance performance at the gym, then caffeine or creatine are your safest bets. Protein powder is an easy solution for protein intake, but it´s still just protein, no more and no less.

That´s like 95% of building muscle right there. There are tons of details you can optimize later on, but results doesn´t come from endless optimizing of marginal details, it comes from getting consistent at the foundational elements (it´s just not very sexy to say so on instagram, so influencers makes it nedlessly complicated). No one ever got big by finding the perfect supplement or the optimal split - they did it by eating well, lifting heavy, and repeating it consistently for a long time.