I'm happy that you have asked me to assist you with your child and hope that you can benefit from my many years of helping parents like you.
This is not unusual at all when solids are started. Is she on any juices?
Are you able to chat right now?
We started giving her apple juice twice a day since last week.
Maybe a tablespoon each time.
Good. I think that will likely take care of it but I would increase her juice and even mix it in her cereal.
Adding any food can change a baby's stools, especially cereal. Apple juice helps loosen stools so keep it up at an increased amount until her stools soften.
Not having a stool for a few days is really not constipation as that really is related to having hard stools, not infrequent ones.
Should we switch from rice cereal to oatmeal cereal?
No reason to do that. Just increase the apple juice to 1-2 ounces twice daily
Will my daughter continue to have bowel movement every 2-3days or will she go back to once a day once her stomach get use to solid?
She will eventually go back to daily stools when she adapts to cereal and it might happen with other foods too but this is very common and expected.
Okay. If she doesn't have bowel movement in another few days. I'll message you back.