If no one has anything in particular you want to do, or want to explore the rest of the chapel, we can do a long rest. Don't forget to subject a food ration too; you need at least one ration or something that can suffice for a ration to get a full long rest. Otherwise you'll only get to heal half instead of the full.

Also for longrest heals, what you will do for those is roll all your hitdie regardless if you expanded all of them, and add your Con bonus multiples by your level. Whatever the total for that would be is how much you're healed. So the formula is Hitdie+Con(Level) = HP healed. If you've only just rested without eating or drinking for that day, you only get half. Do that twice and you'll gain a level of exhaustion, and continue gaining them if you don't eat before you rests. Additional difficulties and penalties may also apply depending on the circumstances, such as cold weather, hot weather, disease, etc.