>>300238>>300325you typically create a map for your videogame using the same game engine you're using to write the code and everything else. the map is really just a collection of 3d assets placed via the editor for your game engine. game engines you can use for 3d include unity, unreal engine, godot, among others. 2d options are basically same, but there are also tons of smaller game engines. there's also special game engines for stuff like doom-likes, roguelikes, rts games, and so on
you can also use games that include map editors to create your map within an existing game. things like valve hammer map editor for source engine mods, warcraft 3 map editor. secondlife is a 3d social mmo that includes 3d building, scripting, land management… you can basically buy virtual land in that game, terraform the land, then build the map
there is no further information to give, without you explaining your game more, but even then you are better off figuring it out on your own