If you ha e access to an iPhone you may find that an apple air tag would work better as you're more likely to be in proximity to loads of people with iPhones.
The tile, without a subscription, works by proximity to your phone, so when your dad wanders off you wouldn't get a location on him just a "last seen at" location and when you "pig" the tile you won't hear it go off as you're in a loud public space.
However the apple air tag I "think" gives you a location of the tag based on the fact it interacts with others iPhones (I think).
So I'd say the Tile definitely won't fit your needs, but an apple air tag might...have a look at that.