Hey mrchntmarine,
Welcome to Apple Support Communities. The information below may help.
When "Frequently Visited" is enabled and you open a new tab, Safari should go straight to the websites you visit most. For more information, click here: Customize your Safari settings on iPhone.
Here's the information on how to customize a start page in Safari: Customize a start page in Safari on Mac.
If you're wanting this information to be shared across all your Apple devices, make sure they are signed in using the same Apple ID, and in Settings > [your name] > iCloud > under "Apps using iCloud" locate Safari. you may have to tap "Show All" to locate it.
Also make sure all the devices are up-to-date. Below are articles that will help.
Update your iPhone or iPad
Update macOS on Mac
If the steps above do not help. Turn "Frequently Visited" setting off on all devices and then toggle it back on. Refreshing the setting may help resolve your issue.
On your Mac, you can pin frequently listed websites in Safari by following the steps below.
1. In the Safari app on your Mac, drag the tab with the website you want to pin to the left side of the tab bar.
2. When the tab shrinks and displays the website’s icon, or the pin appears, drop the tab in place.
3. You can also Control-click a tab, then choose Pin Tab.
Take care.