when ever i upload a retexture mod the texture changes into a flickering messed up thing that changes materials like fence,dirt,nuka cola

You could benefit by reading through http://www.gamesas.com/index.php?/topic/972878-fallout-3-mods-faq/. It explains the basics of mod installation, load order management, archive invalidation, etc. Especially read it if you do not yet understand what those three terms mean.

gothemasticator

that thread didnt help at all maybe i didnt explain my problem well enough when i download a like dogmeat retex it should change him to whats in the images but for some reason it turns him into a fence in the shape of a dog

Open up Fallout Mod Manager, then click the button that says "Toggle Invalidation"

thank you sooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooo much!

Welcome Good luck!

As you start downloading more mods to try out, it will really help to read the readme information for each of them. They will tell you if they know the mod will conflict with another mod, and usually where to place the mod in the load order. Think of it this way, when you start adding mods and never take the time to place them in the correct order, they are going to fight with each other. The mods loaded later will win the battles. Also, always make sure that any files that end with .esm are loaded first (in your load order) and then place the .esp's after them.