Hello, and welcome to these fine fora. I will try to answer your questions for you. I just ask that you understand that I do not speak for the society as a whole. Also, in the future, please make a new thread for each of your questions. You will get much better answers and the threads will not get as confusing.
1. Why do you ask theoretical questions that you and I both know can never be tested? You are asking me to guess, so I will. If you had an infinitely long drill bit, then I would suppose that you could probably drill to the other side, since it makes sense to me that there must be a bottom to the flat Earth.
2. Looking through a telescope produces a two dimensional view of an object. Please do not pretend that you have a magical telescope that allows you to see depth.
3. I believe that there is likely an edge to the flat Earth. As far as I know, no one has been there and returned, though.
4. I do not believe the Earth's surface is endless, but yes, the celestial objects orbit above the Earth.