first how do i take a map of a specific state say louisiana for instance, and use it as a basemap and then if i have gps data info. and i wanna enter that gps data like gps coordinates how do i do that and have it posted on the map precisely?
Well first what level of Mapping do you know and what version of Map3D are you using? Second what format is this specific map in that you want to use as a basemap?
You need to understand that the data (map and GPS points) need to be in a known coordinate system that's is supported by Autodesk.
Now if the map is in a coordinates system and the points are in a coordinate system it helps if they share the same system but not needed. Next is what do you want to do with the points after you get them placed on the map? There's a ton of ways to do what you want but each has different outputs as to what you can do afterwards.