When I go to the root directory in Termux / and then type the command ls. I got the following permission error

ls: cannot open directory '.' : Permission Denied

But inside this root directory, i'm able to access other directories like /sdcard and listing all the files. Is this because my phone is not rooted?

I have tried this:

chmod 755 . (when I'm inside the dir)

chmod 755 /

This will trigger the following error:

chmod: changing permission of '.': Read-only file system

I'm expecting to go to $ROOT and do ls, it will give me list of current folders but I got nothing but error. Accessing the sdcard that is located in root like this is working fine:

ls $ROOT/sdcard