Sorted:

How to optimize system performance in CentOS?

How to install and configure RabbitMQ message queue in CentOS?

How to update the system and software in Ubuntu?

What is the purpose of the sudo command in Ubuntu?

What is stored in the Home directory on Ubuntu?

How to change a user password in Ubuntu?

How can I check the current logged-in user in Ubuntu?

How to create a new folder in Ubuntu

What is Terminal in Ubuntu?

How to find and replace text in Linux?