So my grandson buys a starter set with LC 0r LC+ and wants to run his new engine on grandpa's layout. Sorry, can't do it as you made the mistake of buying a cheap starter set. IF you want to run trains together, throw your starter set away and buy a "real" Lionel train?
Art
He can run it on your TMCC/Legacy/DCS when ever and all he wants, he just has to use the LC or LC+ remote that it came with to control it. You can still run all your trains at the same time using the your remotes. LC & LC+ is fully compatible with all the command control systems, TMCC/Legacy/DCS. Put 18 volts on the track and fire up the remote and you are ready to go.