change hostname in proot

[Win81VMUser]

Hello. How can i change localhost name (root@localhost) to something else like root@vm (like in neofetch)?
After editing /etc/hostname it shows new name only in neofetch but i want make it show everywhere, like in real pc. Is it even possible on proot? Screenshot is from neofetch and from hostname command

[2moe]

cat >> ~/.bashrc <<-'EOF'
PS1='\[\e]0;\u@$HOSTNAME: \w\a\]${debian_chroot:+($debian_chroot)}\[\033[01;32m\]\u@$HOSTNAME\[\033[00m\]:\[\033[01;34m\]\w\[\033[00m\]\$ '
EOF
. ~/.bashrc
HOSTNAME=VM

export HOSTNAME=Win81VMUser-Ubuntu
neofetch

[2moe]

Note: The "PS1 variable" requires single quotes, not double quotes.

[2moe]

After setting the PS1 variable.
Just set the HOSTNAME variable, and it will change the hostname(bash prompt) automatically.