What do I do?

Most likely **** diet.

There could be loads of reasons, but a few possible explanations:
Do you eat enough calories at breakfast and throughout the day?(really important)
Do you exercise/go outside enough? Staying inactive all the time might leave not leave you energised
Is there a chance you have any health issues? Deficiencies like anaemia, lactose/gluten intolerance etc make you tired
Are you doing too much school work/socialising and not leaving any time to relax?
Hope this gives you some ideas..see a doctor if you keep feeling too tired

I sleep for 8hours everyday yet I'm always so tired does anyone know why?

Like tiquismiquis said, it could be something do with with your diet and amount of exercise. If you think that it could be because your diet isn't too nutritious/healthy or you don't do much exercise, you can try to make some changes. If you still feel tired all the time, go and see a GP. I tried to eat healthier and exercise at the gym but I still felt the same so I went to the doctors and they did a blood test and it turns out I have iron-deficiency anemia.

Buy plenty of chicken breasts, green vegetables, dairy, potatoes, whole grains (bread, rice, pasta) and fruIt. All of this can be brought relatively cheap. Eat regularly in small amounts and do sensible amounts of exercise (since you probably don't do it a lot currently, so start small and slowly increase) you should start to feel results within a few weeks and you'll than me later.

If time is an issue, consider cooking meals in batches and freezing them to microwave later on.

I think you need some stretching and exercise.

I sleep for 8hours everyday yet I'm always so tired does anyone know why?

Might be good to see a dr to give you some direction. They can do some bolld tests to check your vitamin levels and things so you know what to focus on. Feeling tired can be becaus eof sooooo many things so having some idea of what might be causing it really helps. If you're just finding yourelf exhausted at the end of the day or tired after something rather strenuous or long (like a day at work or a stressful exam) it's pretty normal and simple changes could help a lot. If you find that you are always tired and exhausted or wake up feeling tired or get so tired you can't do things on a regular basis it may be something medical.

In general, staying well hydrated, eating a balanced diet, getting fresh air and reducing stress are all good places to start. It may sound silly but exercise can help too. Just enough to get your blood pumping, not enough to make you more worn out. Something like a walk or bike ride or maybe a swim. You might try adding a little time to your sleep too to see if it helps. 8hrs is pretty standard but you could see if you can make it 9 and notice a difference.
Try relaxing before bed to get better sleep too. A warm bath before bed or not looking at bright screens can help you get to sleep better.

Might be good to see a dr to give you some direction. They can do some bolld tests to check your vitamin levels and things so you know what to focus on. Feeling tired can be becaus eof sooooo many things so having some idea of what might be causing it really helps. If you're just finding yourelf exhausted at the end of the day or tired after something rather strenuous or long (like a day at work or a stressful exam) it's pretty normal and simple changes could help a lot. If you find that you are always tired and exhausted or wake up feeling tired or get so tired you can't do things on a regular basis it may be something medical.

In general, staying well hydrated, eating a balanced diet, getting fresh air and reducing stress are all good places to start. It may sound silly but exercise can help too. Just enough to get your blood pumping, not enough to make you more worn out. Something like a walk or bike ride or maybe a swim. You might try adding a little time to your sleep too to see if it helps. 8hrs is pretty standard but you could see if you can make it 9 and notice a difference.
Try relaxing before bed to get better sleep too. A warm bath before bed or not looking at bright screens can help you get to sleep better.