Hi VRippers,
Welcome to the Apple Community.
Re: Safari: "Bookmarks have gone"
You might want to check whether you just need to open the sidebar to reveal the bookmarks etc.
ie: by clicking on the rectangular icon on the right of the 3 coloured dots on the left at the top of a Safari page.
For another way to open / close the side-bar and see bookmarks etc.:
Click "View" in the top menu bar : choose "Show Sidebar / Hide Sidebar).
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OR .... If the sidebar isn't the difficulty, and it is not that simple:
You might want to try this:
✽ Quit Safari (click Safari in top menu > choose "Quit Safari" at the bottom of the drop-down menu).
Then
✽ Restart your Mac (click black apple on left on top menu > Choose "Restart" from drop-down menu.
Wait for Mac to start up again ... sign in if needed:
✽ Then re-open Safari (icon in the dock) & see whether Safari seems OK, or whether you still have the same situation.
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Re: "most of the options along the top edge of screen have gone",
You may need to customise the Toolbar with the options you want to see there:
ie: "View" > "Customise Toolbar" and drag any icons you want into the toolbar, ... move them around if you want.
For more info. see: How to: Customise toolbars on Mac – Apple Support
All the best :-)