BD-BDMO 2023 Problem 6

Let $\triangle ABC$ be an acute angle triangle and $\omega$ be its circumcircle. Let $N$ be a point on arc $AC$ not containing $B$ and $S$ be a point on line $AB$ . The line tangent to $\omega$ at $N$ intersects $BC$ at $T$ , $NS$ intersects $\omega$ at $K$ . Assume that $\angle NTC = \angle KSB$ . Prove that $CK\parallel AN \parallel TS$ .