You can get more information about the CentOS distributions, such as installing, configuration best practices, and so on, at https://www.centos.org.
The following website gives you a lot of useful tips and best practices from users in the Linux community, particularly for the Debian distributions, such as Ubuntu: https://askubuntu.com.
This following link gives you information that relates to various commands that work on both CentOS and Ubuntu. You can post your questions there and other community members will respond: https://www.linuxquestions.org.