No there is no point in secp256k1 where x==y
but there is one where x==y+1
x=103219894018170979103981239500535823206309202530631329673674059809050911020508
y=103219894018170979103981239500535823206309202530631329673674059809050911020507
(x**3+7)%P==(y**2)%P => True
So. if we are talking abouy the curve and we have Fp and N :
field Fp is defined by :
Fp = FFFFFFFF FFFFFFFF FFFFFFFF FFFFFFFF FFFFFFFF FFFFFFFF FFFFFFFE FFFFFC2F
order:
Fn = FFFFFFFF FFFFFFFF FFFFFFFF FFFFFFFE BAAEDCE6 AF48A03B BFD25E8C D0364141
your point x,y where
x==103219894018170979103981239500535823206309202530631329673674059809050911020508
y==103219894018170979103981239500535823206309202530631329673674059809050911020507
it is real point as half_mod Fp/Fn , I got problem to explain my english is not so good to technical explain.