I’m assuming these are young chicks that most feeds stores stock in the spring, right?
You do not need grit at this point. POssibly later depending on how you keep them.
All you need to get started is a
quality chick starter feed with the right protein levels. The feed store should be able to help you depending on what chicken feeds they stock.
You‘ll also need the right feeder and waterer for chicks. They don’t feed or drink well from bowls like house birds do and if they fall into the water bowl they can drown or catch a chill and die.
The younger the chicks the more you have to really pay attention to the temperature or use a heat lamp. And something to know about chickens....they all have coccidia. It doesn’t mean they will be sick from it, but it’s present in their systems. Coccidia is opportunistic and can get out of hand if the chicks get too stressed or ill. And it could be spread.
I personally would not keep chicks in the same room with a house bird because of the chance of cross contamination might be too high, both with coccidia and especially with the types of bugs (normal chick germs) and diseases that chicks are generally known to carry unless specifically vaccinated at the hatchery before arriving at the feed stores.
Google raising chicks in a brooder and you can find a lot of information on what to do, however most sites won’t give you the info you need to know to keep everyone healthy. For that you need to google sites about diseases and parasites in fowl. And know that ducks are different than chickens, which are different than turkeys, and so forth.
Now having said that, I’ve successfully raised hundreds of chicks, poults, ducklings, and guinea fowl in the house, however you will find that they grow quick and make a mess even quicker.
Best to keep them away from your house bird and make sure to wash, wash, and wash some more!!
But maybe i will have nothing to worry about cause as soon as ready, they will live outside? Is it safe to feed them grit? It is not good for birds, so why should it be safe for poultry? Very exited today! 
. Thanks for the info... try to get a pic soon... 
