Hey i followed the Perfect server ubuntu 18.04 tut with nginx and i can reach the phpmyadmin url but when i log in to my database it shows me 404 error
The screenshot explains that you are trying to access an HTTP website by https. use http://.. like you did in roundcube.
now in phpmyadmin there is the msg with blowfish secret i changed the secret to 32 charakters on /var/lib/phpmyadmin/blowfish_secret.inc.php reboot but the msg goes not away also there a other msg see screenshot
It might be that the value need to be set in a different file, depending on phpmyadmin version. Have you checked the files in /etc/phpmyadmin/ for this setting? And regarding the other problem, the phpmyadmin database seems to be missing or is incomplete. When you used debian or ubuntu, then you can try to reinstall phpmyadmin with: apt-get install --reinstall phpmyadmin and let the apt installer create the missing database and tables.
You can e.g. use grep to find other occurrences of that settings and it might be that the proposed reinstall of phpmyadmin fixes it too.
this message only appears when i log in not as root user in phpmyadmin at root user it doesnt appear this with configurationstorage