How can I do this so that I don't have this climbing aid on the walls? Or do I need UEFN for this?

Disable “PBWs Generate Ledges” on Island Settings

Note that you may also need to set “Locomotion Preset” to “Custom”, and “Allow Mantling” to “true” to be able to change the ledges option, both also on island settings

I am on UEFN but these options are available on Creative 1.0 Island Settings too
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