I don't need a doctor OR a video to tell me that walking is the best thing for people of all ages.  But it might help you to get started.  Most people are afraid to be outdoors these days - - and with good reason in some areas.  I don't live in an area where that's a problem - yet.  Thank God.

https://articles.mercola.com/sites/articles/archive/2020/01/04/the-walking-revolution.aspx?cid_source=dnl&cid_medium=email&cid_content=art1HL&cid=20200104Z1&et_cid=DM427183&et_rid=783314887

You don't need to spend a dime on "health club memberships", golf clubs or anything else.  Not even a bike unless you prefer biking to walking because it's also good for you.  But I still think walking is the best idea.  In the winter months I walk ALL OVER THE HOUSE so I won't slip on the ice.  Better to be safe than sorry.