Microsoft coins/upgrades sharing

It all depends on the way you've set up your accounts! There are a handful of helpful tools to add security and peace of mind to your payment methods and how they can be used:

Prevent unauthorised purchases on Xbox consoles | Xbox Support

For your specific case, does your son have his own account separate from yours on the xbox? If so, you can set up a family group with you as the parent and your son as the child, which will then open up plenty of options for controlling purchases.

If you battle in the arena you can earn the coins needed to upgrade your equipment. It does take a lot longer than if you purchase coins for your fighter. The choice is yours.

This so-called "upgrade"...not giving me Bingo's that I've won...no coins, no luggage. Also, before this "upgrade" I could play it on my old laptop, which has no problems with Win 10, but since this upgrade, it keeps faulting the WDDM 1.1 igd10umd32.dll
driver...the game crashes every time on it and I had no choice but to uninstall this game from my laptop. This "upgrade" is just sheer incompetence, at the very least. I am beyond disappointment at both Microsoft and Frima Studios for this really bad and horrible
"upgrade".

Thank you, It doesn't make sense then to upgrade to the premium edition, to get more coins, since they are worthless. Thanks again for responding to my questions.

This is how game sharing works

Share these with anyone who signs in to your Pc:

Games and downloadable content from the Microsoft Store

Games from a Game Pass subscription

Account-specific items can’t always be shared. Some examples are:

Game-specific content like Minecraft Skin Mashups

In-game currency such as Minecraft Coins

Certain pre-order bonuses and special edition content that can only be redeemed once