Hello,
Content of the Footer can be changed via Appearance > Widgets. I would recommend using static blocks there.
Watch these videos and read docs – https://youtu.be/-vPCUHnlMIQ https://youtu.be/hmsxW5KF9dg https://xstore.helpscoutdocs.com/article/48-widgets-custom-widget-areas https://xstore.helpscoutdocs.com/article/47-static-blocks https://xstore.helpscoutdocs.com/article/101-wpbakery-page-builder
For example – https://xstore.8theme.com/demos/2/marseille01/ http://prntscr.com/opvljl http://prntscr.com/opvlmc http://prntscr.com/opvlqg http://prntscr.com/opvlut
Regards