Accidentally moved directories under root

Your applications can not run because they want to find libraries and those are misplaced too. Try using busybox directly.

bin/busybox ls

should work as ls and so on.

Lets do another approach. I assume you do not know real root password. Here is a list of libraries that sudo needs:

linux-vdso.so.1 =>  (0x00007ffea6be9000)
libselinux.so.1 => /lib/x86_64-linux-gnu/libselinux.so.1 (0x00007fbbad17b000)
libutil.so.1 => /lib/x86_64-linux-gnu/libutil.so.1 (0x00007fbbacf78000)
libdl.so.2 => /lib/x86_64-linux-gnu/libdl.so.2 (0x00007fbbacd74000)
libc.so.6 => /lib/x86_64-linux-gnu/libc.so.6 (0x00007fbbac9aa000)
libpcre.so.3 => /lib/x86_64-linux-gnu/libpcre.so.3 (0x00007fbbac73d000)
/lib64/ld-linux-x86-64.so.2 (0x00007fbbad5c5000)
libpthread.so.0 => /lib/x86_64-linux-gnu/libpthread.so.0 (0x00007fbbac51f000)

Here is a list of files in sudo package (only relevant ones):

/lib
/lib/systemd
/lib/systemd/system
/lib/systemd/system/sudo.service
/usr
/usr/lib
/usr/lib/sudo
/usr/lib/sudo/system_group.so
/usr/lib/sudo/sudo_noexec.so
/usr/lib/sudo/sudoers.so
/usr/lib/sudo/group_file.so
/usr/lib/sudo/sesh
/usr/bin
/usr/bin/sudoreplay
/usr/bin/sudo

Try moving libraries to the binary, into the same folder. May be it will work. su has less dependencies, but requires to know real root password.