How long it will take a time if people will go to sun from earth by rocket?

The distance from Earth to the Sun is approximately 93,000,000 miles.

The speed of a rocket/spaceship is about 20,000 mph.

So time taken would be 93,000,000/ 20,000 = 4650 hours.

4650 hrs / 24 = 193.75 days.

About one half a year.

These are fictitious figures for a DIRECT flight. However, astronomic bodies, Earth an Sun and spaceships. move in orbits/ellipses. This is normal Newtonian mechanics. Because everything is moving distances would be greater and the time taken would be longer.