(x^3+xy^2+y)dy+(x^2y+y^3+x)dx=0

It is non-exact DE and I'm stuck at making it an exact DE. Need help. Thank you.

so, what have you tried so far?

You need f(x,y) such that
Try writing it as
[y(x^2+y^2) + x] dx + [x(x^2+y^2) + y]dy = 0
With the exception of a factor of 2, that looks a lot like du = 0 where
u = e^(xy) * (x^2+y^2)