Hello and welcome to RootsChat!
You posted this a few months ago, but I was scrolling through the beginners board to see if I could help anyone and found your post. Hopefully, now this has been bumped up to the main board, you will get some more responses.
According to his will extract on FindMyPast, Charles Dean Sr., poultry salesman of Newgate Street, died on 31st October 1832. He died a wealthy man, with his estate being valued at around £4500.
If you haven't seen it, his will can be downloaded for free from here:
https://discovery.nationalarchives.gov.uk/details/r/D259391Unfortunately, I cannot see any mention of relatives other than his wife and children.
There is a burial of a Charles Dean, aged 57, abode: Islington, in St Faith Under St Paul (very close to Newgate Street) on 8th November 1832. His age at death gives an approximate birth year of 1775.
Charles Dean married Mary Elizabeth Hatton on 28th June 1807 in St Clement Danes. The witnesses were Thomas Hutton (presumably Mary's brother, who is also mentioned in Charles' will) and John Townsend. I can see Mary on the 1841 census, aged ~55, with her children: Charles (aged ~24, a salesman), Edmund (aged ~22), Alfred (aged ~20, a tailor) and Henry (aged ~18). They are still living in Newgate Street.
Back to Charles Sr., I don't think there is a father's name on the indenture papers; it looks like it has been left blank.
I cannot find a baptism for Charles in New Windsor; I looked at the Berkshire Wills Index to see if I could find a Dean, yeoman, of New Windsor, but the only Dean was Arthur, butcher of New Windsor, who died in 1713.
Queenie