How exactly do i take off some maps, yet add others.

On your server there should be two files: maplist.txt and mapcycle.txt. Maplist.txt lists all the maps on your server, and mapcycle.txt lists only the selection that people will be able to play, and the order in which they show up.

To add a map, make sure the map's filename is listed in both (without the .bsp extension) and arrange the mapcycle.txt to suit. To remove a map, just delete its entry in mapcycle.txt (you don't have to delete it from maplist.txt). In either case, restart your server afterwards.

If you want to add custom maps, you need to upload its files into the right directories on your server (.bsp files in tf/maps etc.) then add them as above. If you have some webspace, you can also set up a fast redirect to reduce waiting time for players.