And I want them back ! Once they adopt my children out. Will they give them back if I fight for them ?

No, once they are adopted you have no say - you have no legal standing.

No, once they are adopted out, you have lost parental rights. This is the only window frame you have to work with, prior to adoption.

Now is the time for drastic changes---if you don't make drastic change you will not get them back. Something must have caused them to be placed in the care of the state. You will need to have some hard core and mindboggling evidence when you go into court and stand before a judge, so get on it now. You need a lawyer--and income, and must be drug and alcohol free, and if you have a mental issue, that must be in check as well, meaning treatment and medication as well as counseling. You don't have time to skimp here, so if you need some sort of help to make the life changes you require to get the kids back--now is the time to get it.

What does your case worker say? What about your CHILDREN'S case worker?

Have your parental rights been severed, or are your children just in foster care while you rehabilitate yourself?

We need more information, but the short answer is this: If your children have been adopted, you no longer have parental rights, and no legal right to your biological children.

You need to go to any programs they say asap and cooperate with them.

How old are they?
When my kids were older and they took two of mine and adopted one out they said that since my kids were older and knew me and my daughters (unlike a baby or toddler that wouldn't know the difference yet) that I got them sometimes and was allowed to visit them any time I wanted.
When they are 18 the state has no say and they can come back to you too.

Work at getting them back doing everything they require and hopefully they give them back.