THERE IS LOTS OF GRAVITY ACTING ON THE SPACECRAFT!!! WHAT DO YOU THINK KEEPS IT IN ORBIT??????
So if there is a lot of gravity acting on the astronauts from the earth, how can they float???
It is actually because all satellites are constantly FREE FALLING towards the earth, because of gravity. And if you are on a scale in an elevator that is free falling, guess what the scale would read....0!! You would be 'apparently weightless' because everything falls with the same acceleration when gravity is involved. You would not be truly weightless, since there is still gravity acting on you.
Check out this really good video from the Veritasium channel.