If the asteroid that hit the earth causing the dinosaurs to become extinct was millions?

Let me give you some idea of the masses and energies involved.

d(CI) = diameter of the Chicxulub Impactor (i.e. the dinosaur killer) = 10 km

D(E) = diameter of Earth = 6,378 km

m(CI) = mass of the Chicxulub Impactor (i.e. the dinosaur killer) = 2.31E+17 kg

M(E) = mass of Earth = 5.97E+24 kg

E1 = energy yield of the Little Boy atomic bomb dropped on Hiroshima = 6.45E+13 J (15.5 KT)

E1 = energy yield of the Fat Man atomic bomb dropped on Nagasaki = 8.75E+13 J (21.0 KT)

E3 = energy yield of the Tsar Bomb, the largest ever human explosion = 2.10E+17 J (50,000 KT = 50 MT)

E4 = energy yield of the Chicxulub Impactor (i.e. the dinosaur killer) = 5.00E+23 J (120 million MT)

No.  The earth is much much much larger than you realize.  You should get out more...

No.  The Earth is quite big, and has a lot of rotational momentum, like a gyroscope.

You have no idea of the masses you are blithely talking about.

I don't really know what you mean by "knocked off its axis".  What do you imagine that it means ?  But what difference would it make if it did ?  Amongst all the other catastrophic effects of the impact, a slight shift in the axis (IF it had happened) would be unnoticeable.

A million atomic bombs wouldn't knock the Earth off its axis. An atomic blast, viewed from space, is like a pebble thrown into a pond.

The impact was near Mexico near the equator so the axis of the earth would get very little effect from the hit

The spin might have changed

The Largest Nuclear Explosion ever was in the Tundra of Siberia by the USSR

 called the TSAR  Bomb, it was 250 Megaton and the vibrations were felt in New York

It was decided then to Limit their size after that

The Cold War eh ?

Asteroids come into a world of their own, their bang is percussion but the effects can be similar, bar the radiation

The rock that hit Earth was about 6 miles in diameter; the Earth is 8000 miles in diameter - and millions of times more massive.  While the impact was damaging to the surface, it simply didn’t have the force to significantly change the planet’s rotational axis.

probably the orbit was altered slightly and or the rotation rate changed slightly, but it would take a much larger collision to radically change the orbit, such as the one that formed the moon.

no idea what "knocked off its axis" means ...