Should be in "Your Guest Vacation" Documents which were emailed to you. If for whatever reason it's on there, send a DM to X on X (aka Celebrity on Twitter) to ask if you're tendering, they're really good with answering questions yet they're just as pointless as emailing them to complain
We went to Phuket and we stayed overnight in a hotel in 2020 on NCL which tendered. After the tender, we cabbed it to the Phi Phi Island ferry, ferried and stayed the night in Phi Phi. If you book a hotel, email them in advance to ask if you can send them a pic of your passport to expediate check in. And I'll share, our return Phi Phi to Phuket ferry was delayed due to rough conditions and we encountered a moped accident which resulted in a complete traffic standstill for a few mins. We just barely made the all aboard
I recommend telling X you're staying overnight and share the overnight hotel name and/or the address (if staying in a friends/family members home), its helpful to them if there's an emergency