1) In FE theory what is on the bottom of the disk?
There are literally a dozen or more flat earth models with many different answers so i'll just give you some:
1. No one knows.
2. Space
3. Firmament (whatever that is)
4. Whatever material the dome is made of
5. Heaven
6. The earth is infinite you can't dig through the bottom.
7. The earth has a molten core that you can't dig through
2) Hypothetically if I dug straight down using the sun's location at specific times of the day to ensure its straight, lasers etc what would happen? Would I fall out of the bottom eventually?
1. No one knows.
2. You would dig through the bottom of the earth and you would hit Space
3. You would dig through the bottom of the earth and you would hit the Firmament (whatever that is)
4. You would dig through the bottom of the earth and you would hit whatever material the dome is made of
5. You would dig through the bottom of the earth and you would hit Heaven
6. The earth is infinite you can't dig through the bottom.
7. The earth has a molten core that you can't dig through
3) if models that use a dome are true couldn't someone leave Truman style?
1. yes
2. No because there is a firmament
3. no because humans can't survive in space
4. no because the earth is infinite
5. no because you can't walk into heaven
4) if FE is true, scrap looking at a 6 mile canal why can't I stand on the shore of England and see Ireland (specifically Stand on the beach at Blackpool and look at Dublin 135 miles approximately) or Lisbon looking towards New York with a large telescope and see them?
There is a limit to how far light can travel in the atmosphere.