Add a custom header image on WordPress.com

What if I do not see a header option?.

I'm helping a non-profit and in updating their website, I do not see "Appearance" in WP - why not??? Also, sidebar is displaying even though the widget is turned off.

How do you make the header image clickable with a link back to the home page?

I dont have header image section how can i get.?

Thankyu for information 👍👍🙏👌