I’ll be at FLW for basic/osut when our child will be born. How can I request 1-2 days off to be there for csection ? What are my options?

You should get with your recruiter to see about rescheduling basic until after the birth. Unless there's an emergency and a red cross message, they're not just going to give you 1-2 days off to go to this.

The short answer is no. See if you can change your report date.

Honestly the comments already here are Correct. You're not going to be given leave for the birth. In the past I've seen people get access to their phone for a short period to skype/call home after the birth.
Best shot is getting a different course start date. Earlier or later.

Earlier is usually harder, but sometimes units can get you on a waitlist.
Later stinks for the soldier because you have to turn around and leave your newborn.

The army struggle is real.
Best of luck to you. Just dont give up and remember why you're doing what you're doing.