Currently, I have it set to "BlockAll", but it isn't stopping me from clipping into it and isn't allowing the grapple to attach to it.

Hmm, if you can walk though it completely it might just not have any actual collision geometry assigned. Is this a mesh you've imported yourself?

yes it is

How could I go about creating a collision geometry?

Ok, if you open the static mesh in the content browser, and make sure the collision button at the top is highlighted, can you see any wireframe collision models? That button just toggles the visibility, but if you can't see anything with it on, that means there's no collision assigned yet

Ah, and if there isn't any, UE4 can automatically generate collision, if you go to the "collision" tab in the static mesh viewing window, you can see there are a bunch of options for adding various types of collision

Yeah, no wireframe.

Thanks!

Ah right, yes looks like that's it then. Depending on how complex the shape of your mesh is, the auto generating collision may or may not be good enough. In any case, you could try out some of the options there and if it's not good enough, I can tell you how to make custom collision in your 3d modelling program

It seems to be working just fine. Thanks for the help!

Oh I also have a question. How do you create custom Collisions in Blender? In tutorials they use a "block" or whatever and call it UCX_Name of the Moddel. As an example UCX_Palace_floor_asset01. But when i am importing that model there is no collsion in ue4. Did i miss a step?

Sry I mean UCX_Palacefloorasset01

Yeah, you make a separate object in blender make sure it has exactly the same name after the UCX_. So MyMesh would have UCX_MyMesh for example. It sounds like you're doing that right, so I think possibly you just need to change the import settings for the mesh in UE4.
Specifically:
Un-tick "Auto Generate collision"
and un-tick "One Convex Hull Per UCX" (this shouldn't stop it from importing, but might mess up your collision)

Let me know if that was it