There are many possible births for him on FamilySearch:

A: In Suffolk

William Evered
christening: 01 Aug 1738 Bradfield,​ Suffolk,​ England
residence: England
parents: John Evered,​ Mary Evered

William Evered
christening: 01 Aug 1738 BRADFIELD COMBUST,​SUFFOLK,​ENGLAND
parents: John Evered,​ Mary

William Evered
christening: 17 Jan 1724 CAVENDISH,​SUFFOLK,​ENGLAND
death: 30 Apr 1728
parents: Ambrose Evered,​ Sarah

William Everet
christening: 26 Mar 1736 Barrow,​ Suffolk,​ England
residence: Suffolk,​ England
parents: William Everet,​ Elizabeth Everet

William Everard
christening: 25 Feb 1729 ICKWORTH,​SUFFOLK,​ENGLAND
parents: Henary Everard,​ Sarah

William Everet
christening: 26 Mar 1736 BARROW,​SUFFOLK,​ENGLAND
parents: Willm. Everet,​ Elizabeth

William Everard
birth: 1740
christening: 22 Aug 1743 SAINT JAMES,​BURY SAINT EDMUNDS,​SUFFOLK,​ENGLAND
parents: Isaac Everard,​ Ann

Wm. Everard
christening: 17 Jan 1730 Parish of Hartest,​ Co. of Suffolk,​ England
residence: Suffolk,​ England
parents: Sam. Everard,​ Frances Everard

Willm. Everard
christening: 24 Jan 1732 Sudbury,​ Suffolk,​ England
residence: England
parents: Willm. Everard,​ Eliz.

Willm. Everard
christening: 24 Jan 1732 Sudbury,​ Suffolk,​ England
parents: Willm. Everard,​ Eliz.

B. In Cambridgeshire

William Everard
christening: 1724 KIRTLING,​ CAMBRIDGE,​ ENGLAND
residence: Kirtling,​ Cambridgeshire,​ England
parents: Robert Everard,​ Mary

William Everet
christening: 1727 MANEA,​ CAMBRIDGE,​ ENGLAND
residence: Manea,​ Cambridgeshire,​ England
parents: John Everet,​ Mary

William Averit
christening: 07 Sep 1726 Bassingbourne,​ Cambridge,​ England
residence: Bassingbourne,​ Cambridge,​ England
parents: William Averit,​ Mary Averit

William Everard
christening: 10 May 1731 Littleport,​ Cambridge,​ England
residence: Littleport,​ Cambridge,​ England
parents: Thomas Everard,​ Catherine Everard

William Everard
christening: 19 Apr 1724 Kirtling,​ Cambridge,​ England
parents: Robert Everard,​ Mary

William Averit
christening: 07 Sep 1726 BASSINGBOURN,​CAMBRIDGE,​ENGLAND
parents: William Averit,​ Mary

William Everard
christening: 28 Jan 1730 BURWELL,​CAMBRIDGE,​ENGLAND
parents: William Everard,​ Elizabeth

William Everard
christening: 24 Jan 1731 BURWELL,​CAMBRIDGE,​ENGLAND
parents: William Everard,​ Elizabeth

William Everard
christening: 21 Feb 1732 BURWELL,​CAMBRIDGE,​ENGLAND
parents: William Everard,​ Elizabeth

Will'M Everard
christening: 21 Feb 1732 Burwell,​ Cambridge,​ England
residence: England
parents: Will'M Everard,​ Eliz.

I cannot begin to guess which of the above, if any, might be he.
_________________

NA

Their marriage, from FamilySearch:

groom's name: William Everard
bride's name: Mary Turner
marriage date: 15 May 1760
marriage place: Orvsden, Suffolk, England
groom's marital status: Single
bride's marital status: Single
indexing project (batch) number: M01519-2
system origin: England-EASy
source film number: 989611