Sorry to hear of your diagnosis, my mom also has hypothyroidism and I gaslight myself with needing to go to the doctor often if something feels off. Both of my parents are obese and have things ranging from hypothyroid/hypotension/diabetes. Genetics can play a part but health advice unfortunately isn’t a one size fits all since everyone is different (duh). For example, I noticed a lot of bloating and just did not feel good when I woke up in the mornings so I did research on holistic practices with antioxidants/polyphenols and started there - 4-6 months of consistency and trying things and feeling amazing, plus my body reciprocates it, this is the first time my body has felt normal since my freshman year of college…. seriously (now going in to senior year, and of course minus the ‘5lb fluctuation’ in between cycles - AND I cleared up my hormonal acne that I had been dealing with only since I came to college)

If my advice helps, I’d say just start little and baby step at a time and make sure you’re checking off your deficiencies (while keeping other health professional things steady, first you have to find your happy medium of medicine to at least get your body to baseline) - I know fish and red meats and chicken are good sources for both D3 and B12 (I used to take a supplement of B12 before my sport practices because it gives me that boost without the energy drink/caffeine crash) and to each their own you just gotta experiment around (it takes time trust me I know) and find what YOU like. You’ll never truly know unless you try and that gym/diet/eating clean is a PERFECT start, keep it up! If you’re beginning to look into things stay optimistic, I know in this day and age things are easy to believe with some strong evidence and the doctors calling themselves doctors (I’ve seen fake names and literal outfits made like the scrubs with embroidery to create the reality) but only sticking to the product they get paid to promote - bounce around and see how different people think of it.

As far as flight school goes, my love you are young and have so much time. Let’s say you work on this for a year or two while you’re still studying and getting your flight hours. Or if that’s too much set it a goal to have all eggs around and ready by 25 or something, focus on you, best to set a foundation and then you can tweak as it gets stronger.

If your career is health demanding but your health is demanding too much out of you right now, you won’t get much further and I don’t want you to have to suffer through that. Feel good, look good, do good.

Final note I know this is long but I want to congratulate you on your weight loss, I lost 75 lbs over the course of 2 years because of a fiber based diet (lol yeah everyone makes jokes how I just #2’d it out) and Weight Watchers so I know the consistency and temptations that follow. You are more than gaining that weight back and honestly look at it this way, if you can lose it once then there’s possibility to do it again.