Trouble getting New Vegas to Start

[LordNightmaere17]

So I recently got New Vegas and I've been having trouble with getting the mods I installed to work in my game and to get the game itself to start. So I have a shortcut for New Vegas on my desktop from which I can start up the game. But playing on that version of the game none of my mods are present, I checked the data files and it only shows the DLC content. So when I tried to start New Vegas from Nexus Mod manager it goes right into the game then exits out and gives me the Fallout New Vegas has stopped working error. It also no longer starts from the NVSE loader shortcut that I have. I assumed I needed NVSE just like I needed SKSE for Skyrim's mods to fully work.
New Vegas is installed in Steam, not a steam copy of the game but I checked the game's Data folder and it shows all the mod files but for some reason none of the mods are actually working.

[KimberJ]

um you would use the 4Gb launcher, preferably on the task menu , an NMM to set the order beforehand or to download with.

[M48A5]

Could you please explain what you mean by this: "not a steam copy of the game"

[LordNightmaere17]

Sorry for late reply, been busy and stuff.
But It's a disk game than I start up through Steam like most other games and when I installed the game itself I installed it in the Steam folder. I figured that might be important to know if it is just a problem with where it was installed at. But I was told by a friend to have it install in the Steam common folder where all my other Steam games are, so I could get mods off Steam. So now I have two game folders, one in Steam common folder and one under Bethesda, the Data folder in the latter location doesn't show any of my mod files and running the game from the normal shortcut doesn't load my mods. The Data folder in the steam location has all the mod files but the game itself doesn't even start up from the shortcut in my Steam library. Also simply moving the mod files from on data folder to the next doesn't help.