Any NPC BIKINI Competitors on here?

There's a few. Hopefully you don't end up putting your dream ahead of your health?

That said, supplements aren't really a key (they can make nutritional goals easier) more than proper nutrition. Supplements (which can get expensive... and might be worth the tradeoff for a good coach) can help reach nutritonal goals but again if you can't while eating normally.

Calories will be determined by your goals and stats and MFP will (generally) give you a baseline right off the bat if you'll enter them.

Being show ready takes time, patience and dedication... as well as coaching. Not that this is you by any means but there are plenty of ladies seeking the bikini bucketlist who hit the stage unaware of what is aesthetically required and walk away embarassed or frustrated. Take stock of what it'll take (time, at minimum) to really get you into judge/NPC expectations to compete in light of any health issues. If you're good there, you CAN do it and best of luck!