I am not a fan of any stimulant-based fat burner. I wrote a detailed article on the topic many years ago Fat burning supplements

Nothing takes the place of quality nutrition which is by far the most crucial component of not only losing excess body fat but more importantly keeping it off as well. Check out this article on optimizing the master control hormone leptin for fat loss Master control hormone leptin and fat loss

In addition to nutrition, high-intensity cardio improves body composition, health, and energy. Sprinting is one of my favorite forms of high-intensity cardio. Not only does it decrease body fat dramatically, but it is also an incredible mood booster and reduces anxiety. The hormonal impacts of sprinting are also immense as sprinting increases growth hormone levels and improve leptin and insulin sensitivity which are all important for physique composition goals. Without hormone optimization, fat loss goals will evade you. 

If you have never engaged in sprinting training before you need to work into it gradually. Make sure to do some joint mobility work before and start with a few fifty-yard runs to get started. Start increasing the effort after a few runs. You don’t have to make each sprint a maximum effort but you definitely need to be fairly close to derive maximum benefit. if you’re not breathing hard after the first sprint, you’re not applying the necessary effort. Beginners can start with five fifty-yard dashes and work up to ten sprints per workout over time. No need to rush it, let your mind and body adapt to the intense training. 

Sprinting is not for everyone for a variety of reasons such as knee issues. For many, interval training on an elliptical machine will allow you to derive all the benefits of high-intensity cardio without any of the negatives. Start with a five-minute moderate pace to get the body warmed up. Then for the next ten minutes do thirty seconds of an intense effort followed by thirty seconds of a moderate effort. Then wrap up with another five minutes at a moderate pace to cool down and finish off the session. Start with two high-intensity cardio sessions per week and work up to three to four over time depending on your goals. 

If you want to lose fat, you need to optimize hormones as you will never be at your best with estrogen dominance, excess adrenaline, depleted testosterone, insulin resistance, and leptin resistance to name a few. Learn more at Hormone optimization lecture series