How old are they?
If you have a video of them that would be good (upload videos to youtube or similar platform, then provide us a link)
Any photos you would like to share are always welcome.
If they are inside, have you used any cleaning products, sprays, etc. around the chicks. Are you using any air freshener? How much ventilation do you have?
The adults you hatched these from - did they have any respiratory illness or symptoms in the past?
Chicks can snick due to dust or molds in the brooder or from not enough ventilation - those are the first things to look at.
If your parent stock has a respiratory disease, depending on which one, it's possible it could be passed along to hatching eggs or illness can be passed unintended while handling different groups of chickens.
If you notice the sneezing interferes enough that they are not eating/drinking and active, figuring out the cause is important. As mentioned, check environment first to see if anything needs to be corrected. If environment is not the cause, then the next step would be to consider respiratory disease, testing is always a good idea so you know what you are dealing with. Some diseases can respond to antibiotics, but medication is not a cure.
