Umm so just the other day I let my inappropriate little brother online to play call of duty ...

My little brother will probably get it. Anything Call of Duty just gets his jimmies rustled. So I might play an hour or so.

The LAN weekends i had with my brothers and some friends. Spend the whole weekend just playing Call of Duty and some strategy games.

Good old days.

My game duty modern warfare is when I turn it on it says please install multiplayer but I already installed stalled all the packs it and it won’t let me play Online idk why The other day I was playing online I don’t know what happen unless they’re updating
it. Doesn’t say it needs an update so wrong With call of duty Mondern warfare ? Please help out

I'll try to explain, so if my explanation doesn't make sense to you, please tell me, so I can try to explain it differently.

You say the older brother has the GamePass subscription. That means the account of the older brother "owns" the GamePass subscription and purchased games. So no matter where your older son signs in with his account, he has access to GamePass and his games. ANY console the older brother can connect online will allow him to play his games and use the GamePass benefits, as his account "owns" the games and GamePass.

The older brother now can designate ONE console as his "Home Console". This single one console can share his GamePass benefits and games to "anyone" playing on this Home Console.

The younger brother CAN NOT share this, as the younger brother does not own GamePass on his account (so I'd assume from your post). So in order for the younger brother to be able to play the older brother's games and use the older brother's GamePass subscription, the OLDER BROTHER has to set the YOUNGER BROTHER'S CONSOLE as their HomeConsole.

That way, the younger brother's console becoming the older brother's home console will share the older brother's GamePass and games to the younger brother's console and anyone else playing on the younger brother's console.

Or maybe this will make it more clear:

Let's call the two brothers "Aaron" and "Bob".

Aaron has bought GamePass, and "Grand Theft Auto" with his account.

Bob has bought "Call of Duty" with his account.

In order for Aaron to be able to play "Call of Duty" on his console, Bob has to set up Aaron's console as Bob's Home Console. That way Bob shares his games to Aaron's console, and anyone that visits Aaron can play Bob's "Call of Duty" on Aarons console.

Bob owns "Call of Duty" on his own account, and Bob can go anywhere in the world, connect on any Xbox (e.g. at his friend Caesar's house) and play "Call of Duty", as Bob's account on Caesar's console can access the license to unlock the game online. As long as Bob is signed in on Caesar's console, both Bob and Caesar can play Call of Duty.

As soon as Bob signs out and goes back home, Caesar can't play Call of Duty anymore.

Aaron in turn goes to Bob's console and set's the console as Aaron's HomeConsole.

Bob comes back home from Caesar, and thanks to Aaron setting Bob's console as Aaron's HomeConsole, that console shares Aaron's GamePass and "Grand Theft Auto" game.

Let's assume Aaron falls in love with Denise, and he wants to play online with her. When Aaron goes to Denise's console, and sets Denise's console as his new home console, Bob's console loses the HomeConsole sharing of Aaron's stuff.

Now Denise can play Grand Theft Auto online with Aaron, thanks to him setting her console as his home console.

Thanks to that, Bob's console has lost Aaron's home console setting and Bob can NOT play online anymore or play Aaron's GTA.

Since Bob hasn't changed the home console setting when he was visiting Caesar, Aaron can still play "Call of Duty" on his own console, since Bob has set Aaron's console as Bob's HomeConsole (sharing Bob's Call of Duty).

So to sum it up:

In order for the younger brother to be able to play online and access the older brother's games and GamePass subscription, the older brother has to sign into the younger brother's console, and set the younger brother's console as his home console.

If the younger brother has bought games himself, and wants to share these with his older brother, he needs to set the older brother's console as his home console.

And again: Be aware that each account is limited to 5 HomeConsole changes within 365 days!!!

So let's say the older brother set his home console to the younger brother's console last year 2023 in March 20th.

Then the older brother went to his friend and set his friend's console as his home console on May 4th 2023. Then he used 3 other HomeConsole changes on August, October and December 2023 to other friends and used up all 5 changes for 365 days.

In order to set the Home Console back to his younger brother's console, he has to wait until March 20th 2024 to get back one Home Console change.

In May 4th 2024 he'll get an additional home console change back, and the other 3 in August, October and December 2024 respectively.

So try to plan home console changes with that limitation in mind!

If your kids go around sharing their home console setting with friends, and a console in your home breaks and needs to be reset for the home console setting, and they don't have any changes left, it can be a long wait.

Not Being able to use/change your emblem really does suck, im sorry to hear that, that has happened to you, however this is not a Microsoft Problem, its to do with the Developers/publishers of the game, there is nothing Microsoft can do about it sadly, you
will have to get in contact with the developers, i did a little bit of looking around and found this - (may help, may not) -
support.activision.com/Contact_Us

But now you know what happens when you let your little brother play on you account, so i think its best to keep an eye on him when he is using it in the future.