I retired at 62 about 15 years ago, and it is Greaaaat!, best time of my live, really the Golden Years. Always read about people who withered away in retirement, but in my experience, those are the ones whose work was their whole life and who had no other interests in life.
Every retiree I know is as happy as a pig in, er, mud.
I keep busy with a large variety of things, both physical and mental to keep my muscles and my brain exercised.
I strongly recommend volunteering. Check with your city, county or state volunteer bureau. There are a vast number of very interesting and fulfulling opportunities. Many prefer doing something similiar to their careers, others like to find something completely different.
I did work in hospital ERs, helped Special Olympics, did a stint on a suicide hotline (but quit after a year as it got too depressing), tutored for Literacy Volunteers, and now work with the state Foster Care Review Boards.
Think about animal shelters, mentoring kids, groups that clean up highways, visiting nursing homes, helping local police departments or libraries, etc, etc. All this is very good for people who like to keep busy and to help others.
I was too busy working to do such things, but as I’ve been very fortunate in my life, it is a pleasure to give something back.
Good luck and have fun!