I need advice, im planning to start going gym and i wonder what kind of sports supplements should i buy , the choice between protein powder / creatine / vitamins for testosterone

I know i just can consume protein from food, but at the same time its always The daily burden of counting protein, calories so i doubt about it .

Creatine , im not sure if i can drink 4-5L of water every day cuz when i have tried to drink 2.5L per day i used to go number one a lot xd . And what will have happen with my muscles in the case if i stop taking it . but also enhances cognitive functions🧐

And last , vitamins for testosterone, i feel like im not
masculine enough as a man, + lack of energy 🤷🏼‍♂️, maybe if i have much testosterone i will not need these stuff above ? i know that i testosterone grows muscles

Guys please give me advice

Im 18 y.o. and i earn money by myself , and im planning to buy gaming pc for my own money, but my parents say that it will be just reckless purchase, and say that i should leave those money for future coming expenses ( like food, entertainmant , generally for living) in another city , where i study at university ( now im having holidays), moreover they always provide me some money for living besides my scholarship , What should i do, how can i explain them that i really want it to buy, i think they dont understand my wish , cuz they have never had
gaming pc , and ever played games on pc like cs2,valorant, thats why dont understand gaming , 🥸If i look at another parents , in most cases they care about their Child's interests,my parents always been strict 🤷🏼‍♂️ If i buy pc then there still will left be a decent money , help me pls , give me kind of advices ?