Add punctuation: Option 10 CODE OXYGA passenger requiring inflight therapeutic oxygen must prebook and pay for the service at least 7 days prior to travel by contacting the Ryanair Special Assistance Line
A: Option 10 (CODE: OXYG):A passenger requiring in-flight therapeutic oxygen must prebook and pay for the service at least 7 days prior to travel, by contacting the Ryanair Special Assistance Line.

Add punctuation: It was now officially permitted for people to set up stands on the street to sell goods
A: It was now officially permitted for people to set up stands on the street to sell goods.

Add punctuation: I went on a trip with my friends and clicked many photos from my DSLR camera so that I can preserve those beautiful moments in photos Hence even though my camera was displaying Low battery I kept clicking photos
A:
I went on a trip with my friends and clicked many photos from my DSLR camera so that I can preserve those beautiful moments in photos. Hence, even though my camera was displaying "Low battery" I kept clicking photos.