Support Books

Hi Guys, Hope someone might be able help. I am a total noob when it comes to using Linux. I have a server that runs CentOS7 with WHM/cPanel installed. I could do with getting my confidence up on using the CentOS7 operating system and basic linux commands, tools and applications. If anyone knows of any good books,websites or places to go to further my understanding/knowledge of CentOS7 I'd be grateful to learn more. Thank you.