I'd like to create a mod but I can't. I've tried YouTube, I've tried Content_Creation but is hardly helping to me. I just need some help with blender and jbeaming
This is probably your best bet: Introduction_to_Vehicle_Creation Otherwise just start simple, make some basic things in blender, or add or tune things from the official cars. Mod support section is the place to go if you have any issues, we are always happy to help over there.
I've tried to make a simple barrel but I don't get how to add verticies and edges (It has it in meshes on blender in edit mode)
If your problem is the 3D model, you may want to look at some Blender tutorials. That's not something specific to the game, just generic 3D modelling. https://www.youtube.com/playlist?list=PLjEaoINr3zgHs8uzT3yqe4iHGfkCmMJ0P