Hello and Welcome to LinuxQuestions,
There are too many options and possibilities you can use to make a backup of your computer to list them all here. Each user has his/her preferred tool for the job, some swear by Rsync, others by Amanda, Bacula, or other software. Have a look at this short summary of
10 outstanding Linux backup utilities, make a choice and start backing up. Whenever you have questions working with one of those, don't hesitate to post them at LQ.
Kind regards,
Eric