Apartment potty training advice please

Hi, I'm getting a puppy next year, and I live in an dog-heavy apartment building. Because of this, I don't want to have the puppy walking around outside the building for the first couple months while they aren't fully vaccinated.

I am thinking of having a grass turf pad or maybe a real grass pad as a potty area in my apartment, and still having the puppy on leash when we go to the potty spot inside. Does anyone have experience with this? Is it a struggle to get them to go to the bathroom outside if this is how they were trained while they were young?

Any advice or thoughts on how to best navigate this are appreciated. Thanks!