“Not even with three connections.”
For flights, a connection is a transfer to another flight. Not even emphasizes impossibility even under the stated condition. Tina explains in familiar travel terms that even three transfers would not let her visit home by an ordinary airline journey.
“That's a lot to take in.”
Take something in means to understand and emotionally absorb it. That's a lot to take in. acknowledges information too substantial to process immediately. Maya responds to Tina's disclosure that she grew up on another planet without denying it or prying.
“doesn't need a table of contents.”
A table of contents lists a book's sections. Tina now gives Maya the phrase her own friend used in B2-12: a reply to How are you? does not need a table of contents.