Hi,
I installed SuiteCrm via cPanel. I see this image when I login after installation.
I have also attached the error_log file. What should i do, can you help me?!
https://etobilisim.com/5.png
https://etobilisim.com/6.png
Welcome to the community! 
As common with CPanel installations permissions are set incorrectly. Please refer to our install guide and attempt to set permissions via whatever means you have available to you. You could always reach out to the host and request they run specific commands.
find . -type d -not -perm 2755 -exec chmod 2755 {} \;
find . -type f -not -perm 0644 -exec chmod 0644 {} \;
find . ! -user www-data -exec chown www-data:www-data {} \;
chmod +x bin/console