There is many useless info out there so I aim to quickly and in a minimal style explain (almost) all that you need to know to get buff naturally.

Exercises

Aim for a full body or PPL (Push pull leg) split (never do body part splits).
Exercise muscle groups 2 times per week or more
Focus your exercise selection on compound movements (bench press, squats, overhead press, deadlift) + freeweight/cable isolations
Don't buy a personalized plan, find a suitable plan for free on YouTube or make your own
Use double progression and Top/Backoff sets for weight progression
Go for a 5 to 10 rep (repetition) range and 3 to 5 set range, focus on training to failure or 1-2 reps short of failure

Diet and supplements

Almost all supplements except of protein if you cant get it enough through food are scam and a marketing trick.
Use calorie calculator to calculate your daily calorie intake that you need to bulk or cut. There is also a calculator on this site for needed macros.
Don't let get the calorie numbers get into your head! Just bulk. If you are questioning, Just bulk!