is there any age limit to claim long term disability and my policy says term 10 year for extreme disability and what will happen if my insurance expires and I was not able to file a claim and my disability is more than 3 years.

Each policy will have their own provisions, but often LTD ends at 65. If you became disabled while you had coverage, then you should certainly attempt to apply. If may be denied based on timelines, but if that's the case, we can still review and see if you have any options for recourse.