I also do not smoke, never done drugs, and do not drink or anything of that nature
You're still a young person so there is a good chance that no long term damage has been done yet. Having lost that much weight in my life I can attest to the improvement of your overall quality of life, it is very amazing.
The most important thing is to discuss your weight loss plans with your doctor and let them approve you medically for what you're going to put your body through. Also, make sure to lose weight under your doctor's care, don't get suckered into weight loss products or fad diets, they can do long term damage. It's very simple, a 3,500 calorie deficit over and specific period of time equals one pound lost, it's not that complicated. I went low carb, but not true Keto as I found that too demanding and not necessary. Get a good carb tracker and set a daily carb goal with your doctor. I like low carb because it allows you to focus on what you can eat and not what you can't so much. In my case, a typical 2,500 calorie day equates to an allowable carb number around 200 and I try too keep it under 100 which is not very difficult in time. I lost 70 lbs in the first 4 months and another 30 in the following 8 and have been able to keep it off.
Keeping a healthy body weight will certainly help to increase your life expectancy, just make sure to do it right and good luck. Jon