apt update
apt upgrade -y
apt autoremove -y
apt autoclean -y
nano /etc/sysctl.conf
net.core.default_qdisc=fq
net.ipv4.tcp_congestion_control=bbr
sysctl -p
ufw allow 22/tcp
ufw allow 443/tcp
ufw enable
nano /etc/ssh/sshd_config
Find and change #Port 22
to Port 443
, save and exit.
systemctl restart sshd
exit
ssh -p 443 {ip_address}
Then
ufw delete allow 22/tcp
adduser username --shell=/bin/false
deluser user