involving in charity or community work is also good, as you would derive positive energy from helping other people who express gratitude for receiving your good deeds

Assuming you do have mortgage payments, the biggest unexpected outflow in your retirement will be medical costs; subsistence living should not cost much; the level of luxuries or higher standards of living depends on your means.

Try these links for elder academy: https://charm-retirement.com/classes/

My son got a grade of A only in Chemistry, Biology and Pure Maths. No A* at all. Is there a chance to get an interview invitation?