fish_user_paths are the alternative for $PATH in fish shell.
But how do I find out, what’s in my fish path?
echo $fish_user_paths | tr " " "\n" | nl
This gives you an array of path environment variables.
You can erase a path with
set -e fish_user_paths.
Be aware that the array is mutable, so if you delete an item, another one will take its place.