how can I make folder accessible by one user

Sorry for being late!

I tried to log in to the server from the user who has the problem and here is the log.

Oct 16 18:42:17 ibrahimh sshd[9947]: Accepted password for root from 2X.X9.18.X0 port 16041 ssh2
Oct 16 18:42:17 ibrahimh sshd[9947]: pam_unix(sshd:session): session opened for user root by (uid=0)
Oct 16 18:42:17 ibrahimh systemd-logind[789]: New session 882 of user root.


Oct 16 18:45:57 ibrahimh sshd[10048]: Accepted password for mouath from 2X.X9.18.X0 port 16394 ssh2
Oct 16 18:45:57 ibrahimh sshd[10048]: pam_unix(sshd:session): session opened for user mouath by (uid=0)
Oct 16 18:45:57 ibrahimh systemd: pam_unix(systemd-user:session): session opened for user mouath by (uid=0)
Oct 16 18:45:57 ibrahimh systemd-logind[789]: New session 883 of user mouath.
Oct 16 18:45:58 ibrahimh sshd[10142]: fatal: bad ownership or modes for chroot directory component "/var/www/"
Oct 16 18:45:58 ibrahimh sshd[10048]: pam_unix(sshd:session): session closed for user mouath
Oct 16 18:45:58 ibrahimh systemd-logind[789]: Removed session 883.

What’s in the error log? Run this right after you attempt a restart of sshd:

journaltctl -xe

This is a good tutorial on how to do that: https://www.tecmint.com/restrict-sftp-user-home-directories-using-chroot/

Make sure to disable SSH login just like the tutorial shows. Otherwise it’s easy to circumvent the restrictions.