Question

why do the astronauts feel weightlessness inside the orbiting spacecraft?

Answer 1

They are weightlessbecause there is no external contact force pushing or pulling upon their body. In each case, gravity is the only force acting upon their body.

Answer 2

Hello friend,
Here's your answer:

Earth-Orbiting astronauts feel weightless.
This feeling also can be felt when the riders of free-falling amusement park ride or a free-falling elevator. This feeling is weightless.

They are weightless because there is no external contact force pushing or pulling (Applying force) upon their body.
In each case, gravity is the only force acting upon the body.

Hope my answer helps you.