Can i add my son’s xbox account to my email?

You can only have 1 account per email. You wouldn't have to buy the games twice either. As long as you set the console as your Home, he can access your games. https://support.xbox.com/en-US/help/hardware-network/console/my-home-xbox

Thanks for the advice.

As myself and my son very likely just play in our PC, not on a console, so may I recap if my understanding is correct l:

1. Claim the game pass key under my own email address in my Microsoft account

2. Through my Microsoft family, my son can share the subscription as my family member

3. Register my xBox account same email as my Microsoft account email which claimed the game pass

4. In my son's laptop, he also create his xbox account using his email address which is the same as his email in my Microsoft family setting

5. In my son's laptop, somewhere in his xBox setting, add my email as the Microsoft store account. I think it is how his xbox account get access into the game pass.

I will try out how the step 5 when I get the game pass key.

In the meantime, is my understanding correct that if my son login his xbox app and I login my xbox app at the same time in our two computers, both of us can play our own games at the same time?

Is there any limit of xbox account that can add my Microsoft store account?

And is there any limit how many of those accounts can play games at the sane time?

Really appreciate your advice

Cheers

Are you wanting to add his email as an email used to sign into your account?

As long as his email is not currently a MS account you would be able to do that by going to account.microsoft.com/addassocid and add his account as an alias to your account that way he then can use his email address to sign into your account and you would
still be able to use your email address to sign into your account also.

If his email is already a MS account then you would not be able to do that.

So, he could use a gmail address?

Yes as long as he is not using it on another MS account