DOS Games Discussion

How Do You Make Games With DOSbox?

You don't.
DOSBox is a DOS emulator, which means it's designed to act like DOS.

You can create games that are designed for DOS and play them in DOSBox, but you can't make games with it.

Look here: http://www.cplusplus.com/doc/tutorial/
And here: http://www.bloodshed.net/devcpp.html
And maybe even here: http://libsdl.org/
And then here: http://lazyfoo.net/

These aren't for DOS games, but you can make games that have a DOS feel.

Alternately, you can try game making software (I called 'em "Game Creation Systems" back when I first made DOSGames.com) like these:
http://www.dosgames.com/g_gcs.php
These can be run in DOSBox and can be used to make games.

Another good option is GameMaker, although it is Windows-based not DOS:
http://www.gamemaker.nl