Hi, I'm already talking to you on the other thread, but would like to answer these questions so others may know as well.
Pigeons are not like chicks. You cant get day old ones and raise them. They need to be raised by parent until weaned at about day 30.
When you do succeed to get some of those pigeons from parking garage this is what you will need to do. Keep them prisoners. It may sound like a cruel, term, but is not a cruel process. This simply means that you keep them to breed and raise young families for you. You provide them

and great housing, as well as great diet of food. You do not let them fly free. They, in the beginning will most certainly not return if released.
If you want them to return to YOUR loft, they will need to be HOMESET.
It is a process that is not always successful with adult pigeons. Once they have freedom, they often return to their original home. The parking garage in your case.
The pigeons that are born/hatched and reared in your loft can be trained to return to your loft. After raising about 3 to 4 clutches of young, the parents are at a stage to be possibly homeset to your loft. Some are easier, and earlier, while the top homers just wont have
nothing, except their original home.
The youngsters do not follow the parents,
unless too young,(and not homeset) and take flight with them. In short order they run out of energy and end up getting lost. Not able to return to your loft since not trained gradually to do so. Parents just keep going whether junior follows or not.
The whole pigeon keeping process is lengthy to explain in one sitting/writing session.
Check out these two other threads, and read the plethora of information contained there.
One is started by the person you are on other thread. Other is started by a very knowledgeable person in ALL PIGEONS. There are many GREAT CONTRIBUTORS on those threads. I subscribe to both as well.
https://www.backyardchickens.com/threads/uk-pigeon-owners.1244157/
https://www.backyardchickens.com/threads/pigeon-bulletin-board.1174207/
AS ALWAYS,,,,, WISHING YOU BEST,,,,
