You can tell — or not tell — whomever you want about your ostomy
It's up to you to decide who to tell about your ostomy surgery. It may make sense to tell the people closest to you. These people may be worried about your recovery, and explaining your ostomy may ease their fears. Talking with loved ones is also a healthy way to cope with your emotions.
Acquaintances may be curious about why you've been away from work or know that you were in the hospital and ask about your illness. Think ahead about what to say when questions arise. You could say you've had abdominal surgery or use another basic description without going into details if you're uncomfortable discussing your ostomy with people you don't know well.
Other people will need to know about your ostomy for practical purposes. If you don't have a desk or locker at work to store extra ostomy supplies, for instance, you might need to reveal some details of your ostomy to someone at work so that such arrangements can be made.
Some people keep their ostomy surgery private, and others prefer to tell anyone who asks. Who you tell is up to you, but you may find you're more willing to discuss the details as you become more comfortable caring for your ostomy.