FAQ block is a way to put information on your page in a compact manner. You enter all the information, and your visitors can view it.
Yes, but the text must be divided into 2 parts. The first, which is always shown, should be placed in the "Text" block. The second (hidden) - in the block "FAQ", hiding behind the title "Read more" or any other.
The minimum distance between question headers will be if they are placed in the same "FAQ" block.