This site is set up to use the newer method of WordPress updates: “block” editor. However, I suggest you review both “classic” and “block” documentation on my site, as desired, as that is the order I wrote them and there are some resources on the classic page.
Remainder of documentation below is specific to this site.
The areas you will use most are Media, Pages, Appearance, and MetaSlider.
Slider content is created in MetaSlider (bottom of admin left nav) and then placed in the Page. In MetaSlider, toggle between slideshows by expanding Browse Slideshows upper left. New slides, new slideshows, and Save are upper right. I noted that I used two sizes. See other instructions in Documentation on my website.
I hid the page titles so that the sliders would tuck right up against the header (and behind it on larger screens).
You may want to create a Guests page, not include it in the navigation, like a private page, and manually give people the link. Heat page?
You may add your own helpful hints to this page as well.