What kind of vitamins should I take because I'm constantly feeling tired even after 8+ hours of sleep?

Hard to say. The 2 most common nutritional deficiencies in the u. S. Are vitamin d (if you live north of atlanta, ga or you do not get enough sun exposure without sunblock) and essential fatty acids (omega 3s) if you do not eat wild, cold water fish on a regular basis. Be sure your thyroid level is okay, you do not have sleep apnea and that you are not anemic, three common causes of fatigue.
Anti oxidants. Daytime sleepiness is multifactorial. I would suggest getting labs done including a thyroid level, vitamin b 12 and vitamin d level as well as a cortisol and iron level. If unrevealing a sleep study may be needed. Make sure you are exercising daily and getting proper nutrition via fruits and veggies... 7-13 servings daily.