> I install nothing in it except Apple Freeform. (No distractions)

How do you uninstall Safari? That's the most distracting app of all.

It’s not exactly that, but:

Open Shortcuts.

Go to Automations.

Create one, for App, when Safari is opened, run immediately.

Create a new blank shortcut.

Add one action: go to Home Screen.

Now when you open Safari, it instantly closes again. You can disable that by turning off the automation. It’s more of a slap on the wrist than a handcuff, but a reminder that you don’t want to use the app on that device.

You can disable javascript which in my opinion makes it unusable.