The Nano S has been discontinued (with other models too): https://support.ledger.com/article/360010500620-zd

Personally, I wouldn't buy a ledger device especially after the whole recovery system they pushed some time ago (not sure how things are right now, and if they have made any more clarifications, etc. I haven't been following).

As for your second question, you can check this article: https://support.ledger.com/article/4404389367057-zd