My Mom Has Cops, Asthmato?oas Had Throat Cancer. She Had

My mom has cops, asthmato?oas had throat cancer. She had chemo and radiation. In remission for 8 years Twice in the last 6 months she has " choked" on water. And can not breathe. What do I do when this happens? All I know is to get her to a fan blowing in her face until she can breathe enough to catch her breath to be able to take her inhaler. And what do I do if one day she is unable to catch her breathe? What do I do while waiting on ambulance to get here if I need to?