How shall I introduce new chickens to a spoiled chicken?

[clucking with my chicken]

Hey guys, so I have this chicken named Oreo and she is the only chicken,
she was getting builled so I decided to take her home with me as a young teenager chicken, 18 weeks to be exact.
I have had her since 2018 june and she is so spoiled.
we once brought her a friend, she did the pecking order then everything was fine, but then the friend died for no reason.
i think that she might of not been used to Oreos germs and I did not give her a chance.
now, we and getting a much bigger area for our chicken, and we are thinking about added 6 chickens to oreo as friend.
how shall I introduce them what shall I do?

 

[aart]

Are you going to get day old chicks...or....?
Just how big is your new area?
Dimensions and pics would help here.

This might help:
https://www.backyardchickens.com/articles/introducing-a-single-hen-to-an-existing-flock.71997/

As might these tips about....
Integration Basics:
It's all about territory and resources(space/food/water).
Existing birds will almost always attack new ones to defend their resources.
Understanding chicken behaviors is essential to integrating new birds into your flock.

Confine new birds within sight but physically segregated from older/existing birds for several weeks, so they can see and get used to each other but not physically interact.

In adjacent runs, spread scratch grains along the dividing mesh, best if mesh is just big enough for birds to stick their head thru, so they get used to eating together.

The more space, the better. Birds will peck to establish dominance, the pecked bird needs space to get away. As long as there's no copious blood drawn and/or new bird is not trapped/pinned down and beaten unmercilessly, let them work it out. Every time you interfere or remove new birds, they'll have to start the pecking order thing all over again.

Multiple feed/water stations. Dominance issues are most often carried out over sustenance, more stations lessens the frequency of that issue.

Places for the new birds to hide 'out of line of sight'(but not a dead end trap) and/or up and away from any bully birds. Roosts, pallets or boards leaned up against walls or up on concrete blocks, old chairs tables, branches, logs, stumps out in the run can really help. Lots of diversion and places to 'hide' instead of bare wide open run.
Good ideas for hiding places:
https://www.backyardchickens.com/threads/a-cluttered-run.1323792/