eh? Like... what? How do you mean?
I played french horn at one time, and have sung all my life. Getting effective breathing is not something easily described in words; it helps a great deal to have a coach watch you.
Perhaps the most important thing is to remember that your breath support for any wind instrument or singing comes from the diaphragm. If you aren't using the diaphragm, you are in grave difficulty! (by the way -- don't even try to play or sing immediately after a good meal; your diaphragm has no room to move).
There are a number of breathing exercises which can help with control -- but I would strongly suggest working with your teacher, if you have one, or some other coach, since so much of it is physical (a good voice teacher or vocal coach may be more helpful than an instrumental coach).