Is the earth rotating on it's axis?

Answer 1

To the extent that it's simply the imaginary line about which the Earth rotates, no. However, Yes, with time, but relatively to the plane of the Earth's orbit, not to the planet itself. It precesses.

Answer 2

Indeed it is, that is why the Sun and the Moon and the Stars all appear to rise in the East and set in the West. The approx circular path of the Earth around the Sun is called 'the plane of the ecliptic', and it takes the Earth 1 year to travel round this path.

The spin axis of the Earth is tilted approx 23o to this plane, and it is this that gives our seasons, and indeed why the seasons are opposite in the two hemispheres.

At the point around the path when the northern hemisphere is tilted towards the Sun, summer will bless those in the north.

Six months later, the Southern Hemisphere will have travelled to the opposite side of the ecliptic plane, and will enjoy the tilt to the Sun, and will have summer.

Note that the tilt of the spin axis stays fixed in position relative to our Milky Way galaxy. It appears fixed with regard to space.

[But does wobble and precess to a tiny amount, but we can ignore that here.]

Answer 3

Yes, the axis of rotation of the eath is tilted with respect to the plane of its orbit about the sun. The tilt of the earth's axis of rotation with respect to the sun gives us the change of the seasons.