You should consider getting a sleep test. As far back as I can remember, I have always been tired and sleepy through the years. I just attributed it to being on less sleep due to my erratic schedule. But I was diagnosed with Sleep Apnea at 29, after likely having it for a couple of decades or so.

Been using CPAP for almost 5 years now. Everyday is fantastically fresh with a regular ~7 hours of sleep. Can't recommend it enough. I am also on path to see if my Blood Pressure medicine can be stopped - since it is understood to be the side effect of Sleep Apnea in my case. Should become clear in a few months.

Also, been active for a year. Started just walking in the evening mandatorily - sometimes listening to podcasts, and other times just using it as a break from everything digital. Then, after a few months, split the walk-time into a morning and evening routine. Probably been regular at it for about 395 of the last 400 days. It's a habit now. Added running to the routine but it is a bit erratic still. Want to add HIIT / Weight-training to workout routine, but that hasn't stuck at all and will try again in a while.

As to the results, I am almost 11Kgs lighter from my max weight, feel healthy, BP is almost always normal, BMI is close to normal, resting heart rate has dipped significantly, and so much more. I track a ton of this info as it can help you stay motivated on the slow, low and tiresome days. :)

Wish you all the best - experiment and find something that suits you best!