Trouble eating since childhood is common?

Recently diagnosed and starting medication today. All my life i’ve been skinny/underweight but couldn’t point why. I get exited about good food but get bored of eating easily, i also eat súper slow bc I talk non stop or use my phone. When I’m sad or anxious I just skipp meals bc I just Can seem to go to the fridge? I Can Cook nicely and is a major interest for me, learning spices and recipes but i never finish my súper elaborate meals I do the exact way I like!! I also happen to have 1 hour break with the company paying for my lunch from any restaurant I like in downtown so I’m always the first to go out but I just like trying the new meals. The only time I put weight is with apetite stimulants and obsessing with a breakfast like oats but it always wears off after a couple weeks Is this common?