Chokkie...use this site to get an official statement about your Old Age Pension, ie your State Pension.
https://www.gov.uk/calculate-state-pension
You will get a reply back in the post within about 10 days and it will give the exact date when your State Pension will be paid to you and how much you will get. Done and dusted !
You can retire at any age you like. All that retirement means is that you have stopped working permanently. But exactly when your "works" pension is paid to you and how much you get, will depend on your employers scheme. You may have many previous employers and you may have "preserved" pension coming to you from them as well.
I would start with your current employer ( I am presuming that you employed, not self-employed ) If you have not got a Pensions Handbook, contact your HR Dept and they will send you one. It will give clear guidance as to the exact earliest age that your works pension will be paid to you. You should also have had annual pension statements, although some employers are a tad tardy with supplying them these days. If you are a Member of a Trade Union, they will also be able to assist.
Do the same with any previous employers that you may have had.
This next bit may be obvious but being retired doesn't mean that you can't start work again ! Lots of people these days continue to work, either part time or full time, while still receiving a State Pension and/or works pensions.