Answers
The Agent answers from your material
Which sizes and finishes do you have? How thick is this door?
The answer is in your published product material: sizes, finishes, materials, whatever you wrote in the specifications.
How much fits in a 20ft container?
If you wrote the loading quantity into the product specifications or the FAQ, it answers from that. If you did not, it does not estimate: it tells the buyer it will check.
What is the MOQ? How long is the lead time? Which port do you ship from?
The answers are in the company profile and FAQ you wrote: MOQ, typical lead time, shipping and ports.