3D branches

hi everyone. I’m a student now and a fresher in grasshopper. now I’m trying to create a structure like a tree growing on the wall. now I only create the branches but don’t know how to fixed it like what I want.1. it is not smooth at the connection points. 2. I don’t know how to create the wall at the top.
Could anyone help me? thank you very much.
3D branches.gh (9.0 KB)

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