The good news is that some of them can help. The bad news is that there is a lot of marketing BS selling products that are totally worthless.
Disclaimer: This guide is for educational purposes only. This is not a replacement for a consultation with a medical professional.
Before considering any supplements, make sure you eat good food, have enough activity, and sleep 6-8 hours a day. If you are lacking any of these, then fixing that first will bring you better results than any supplements.
Assuming your base is in good shape, now let's get into it.
1. Creatine Monohydrate
Main performance enhancement is during repeated short bursts of intense activity typically up to 2.5 minutes at a time. Can be sprinting or weight lifting. Do not expect to get much value for endurance sports like distance running, cycling, or swimming.
Regarding usage. There is a loading dose of about 20 grams per day of creatine (in four equal portions) for 5 to 7 days and then 3 to 5 grams a day. To see the effect, you need to take creatine for several weeks or months.
2. Protein
Protein is essential for the repair, construction, and maintenance of your muscle mass. That means you need to have enough protein. And if you are an athlete, then you need even more.
Regarding usage. Base is 1-2 grams of protein per kilogram of your body weight a day. That should mostly come out of your food. If you do high-intensity workouts, then add 0.3 grams per kilogram of body weight every 3 to 5 hours, including before sleep and within 2 hours after exercising. That can come out of supplements. It's also safe to take more than what you need, except that there is no benefit.
3. BCAA
BCAAs are important for muscle growth. Roughly 35% of the amino acids in your muscles are BCAAs. But no worry, if you eat high-protein food, then you should already consume enough of them (10-20 grams per day). Supplements are great if for the time you are not sure about the diet.
Regarding usage. Supplements can boost you up to 20 grams per day.
