sudo: /usr/bin/sudo must be owned by uid 0 and have the setuid bit set
That kind of problem.
Option 1
Control + Alt + F3
log in as root and live without sudo
Option 2
Open a terminal
ssh root@127.0.0.1
and log in as root
Option 3
copy this to a file named /tmp/armbiansudo.txt
chown root:root /usr/bin/sudo
chmod 4755 /usr/bin/sudo
chown root:root /usr/lib/sudo/sudoers.so
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