I know this will sound like crazy advice but ask around and find a good vet in your area. Consider getting pet insurance on your pup as soon as it comes home. Get it microchipped as well, that will help if it is ever lost. There are always high risk times for dogs needing vet care but the heaviest is from puppy until about 2 years, then as they get older and start needing more care. But you’ll want regular checkups for the dog as it ages anyway, insurance usually helps with that.
I’d also recommend crating your dog at night. Get them used to the small crate space and they will stop using the bathroom in there immediately. But use that to help get them on a schedule to go outside as soon as they come out of the crate in the morning to use the restroom outside. You can read up on crating if you’ve never done it, just understand it shouldn’t be a place for punishment, but rather for rest and quiet time.
And hash out with your partner now for the times best for both of you to handle bathroom trips outside, walks, feeding, etc. You’ve both had dogs but a dog in a relationship means someone having that duty at a particular time. Talk through it now to avoid arguing over it later. You might also both remind each other that younger dogs or those new to an environment make messes. It’s part of pet ownership. Shrug it off and try not to get mad at your dog for things they do. Again, you’ve both had dogs, this should be easy for you both. Dogs are all about routine. Try not to vary the times when they have bio breaks or food too much, especially until they get housebroken.
EDIT: Also, none of this really matters here. We need pics of your new pet!!! :)