The GPS on my Galaxy Note IV is often wrong
Nope. Since there isn't anything technically wrong with the gps in your phone and it's just the location of where you are that throws it off, the best thing to do is just go outside and see if the signal is stronger from outside the building or deal with it. 
Google maps doesn't currently have any features that allow users to correct their location. You can type it in the search bar if you're trying to get from your current location to another but it won't exactly "stick".

Hope this helped.