more than one console in my home

The Xbox that you do not use as often, set that one up as your Home Xbox.

https://support.xbox.com/en-US/games/game-setup/my-home-xbox

Then Xbox that you do use often, do not setup as a Home Xbox. Use it as you normally would and log in with your Gamertag to play. Now, if you have a friend over and want to play together then they can log in to the Home Xbox and use games from your library
and will even have Gold access while they are logged into that Xbox. If they don't have a Live account then they will need to create one (or you can create a second live account for people to use).

Basically games comes with two licenses, one attaches to your Gamertag and the other attaches to whatever you have set for your Home Xbox for that Gamertag. So I have an Xbox upstairs for the kids (Set as the Home xbox for my Gamertag) and I have one in
the office for me (No home set, I login to it). I login to the one upstairs and purchase/download/install games then logout. Now my kids can login and use that Xbox to play games from my library. They can even play same games online with me if they use
the Upstairs Home Xbox and I use the Xbox in my office.

Yes and you have to share the game through the xbox home feature.

Your brother will have to pay for his own games and gold unfortunately

No. Its true you can only have ONE home console. Not sure who told you that support could let you have more than one but thats definitely false.

I have one in the Living room.

My 8 yr old son has one in his room.

& my 12 yr old daughter has one in hers.

Mom shares mine for Family-Pack status.

All are model S and loved <3

May setup a PS1 for FFTactics and a N64 in bedroom that we are switching to, for Rampage 2 & Conquers.