By backing up your site, you are being responsible for your website as a business. It is your responsibility to backup regularly! That way you are protected in case you get hacked or something happens, and you lost your content.
The plugin I am using in this video is called UpdraftPlus. Here is the link for download:
https://wordpress.org/plugins/updraftplus/
Step by step pictures on how to do back up (after you have download the UpdraftPlus from the plugins):
Step 1: At the top of the bar, click UpdraftPlus and choose Backup/Restore option
Step 2: Now click on the blue Backup Now button. It will open small popup window on like shown on the Step 3.
Step 3: Choose first two options (default) like shown in the picture and click the gray Backup Now button from the popup.
Step 4: After the backup process is complete you will first click on each of the data sections from the bottom backup list (horizontal 1-5 numbers), and then download each one to your computer (vertical 1-5 numbers).
You can then safely keep it on your computer and store it do your dropbox (or what ever cloud storage you are using) for free.
Otherwise, Dropbox backup options is premium and you would have to pay it. This way, you can do it for free
Write if you have any questions and I will try and help :)