Welcome to the forums.
Like Cipscis said, this part is for questions about making mods. Mods are made with a tool called http://geck.gamesas.com/index.php/Main_Page (Garden of Eden Creation Kit) A powerful tool that allows you to script, design and plan your own levels and mods to add to fallout 3 for PC. You can add your own NPC's, custom items, weapons, clutter, clothes, armor, places, storylines, quests and so much more. It really is a fun thing to learn how to use and some people have made really really fantastic mods. If you are interested in it Cipscis knows just about everything there is to know about scripting, (he is a pro) and has many tools in his Signature for optimizing scripts, checking them for errors, and a few incredibly useful tutorials. If you start using The G.E.C.K. and have any questions, ask in this section of the forums.
Gunmaster95