Hi, it's very easy,
I have below suggestions for you:
1. If you have any Customized extensions on your environment, then in that extension you can create you new al object for the page extension - but this will add these 2 fields for the user but you can handle this by extending the page and setting Visible = false in the extension, later the user personalizes these fields based on their requirement.
2. If you don't have any customized extension and you want to do it from UI then make sure you have proper permission so you can use Design instead of Personalize, and add the fields on the page, by default this will add the fields for every user.
If you are using suggestion no. 1 then here is the code:

Make sure to verify, if it helps.