The first photo was taken at 39,000 feet by a teenager last year, and clearly shows the curvature of the Earth
It actually clearly shows the effect of the lens. From that height you still can't actually see the curvature.
I'm no flatty, but that's not what the picture shows.
Sadly, I have to agree - as an RE supporter - you shouldn't be able to see that much curvature at that altitude. So most likely the lens provided some distortion.
At 39,000 feet, the horizon is dipped 3.5 degrees below the horizontal...but in a typical 60 degree field-of-view camera, the difference at the sides of the picture compared to the center is less than a pixel.
The ship-over-horizon thing is real - but it's very hard to prove it because we know that close to the surface of the ocean, the rate of temperature and humidity change in the air causes enough refraction to bend the light rays and make the results VERY hard to determine conclusively. This is why you so often see things like mirages when you look towards the horizon.
I can tell you from past experience with Flat Earthers that these photos will not convince ANYONE.
Check out some of the other "Disproof" threads here for much less debatable evidence.