Indeed, welcome to the Guild! As for the unable to find a gaming group, as Redrobes mentioned you should definitely look into Virtual Table Tops. There are quite a few out there and they offer various strengths and weaknesses. Some cost money and some are free. You can search this board for tags and words. The best tag to search for would be VTT and for words you can search for the names of the various VTTs that people here use and have posted about such as, in alphabetical order, Battlegrounds, Fantasy Grounds, MapTool, OpenRPG, and ViewingDale.

As for the mapping part, you are definitely in the right place and feel free to ask lots of questions and get advice on your maps. That is what we are here for.