If it is close enough then it can be seen
You see it during the day, the Sun is a star and it is the nearest star to Earth.
There are no stars in the Earth. For the biggest star in the Universe, see the related question.
The closest star to the Earth is the Sun. See related question.
Sirius
Yes.
The Sun
A shooting star, which is within the Earth's atmosphere.
The planets visible without the aide of a telescope are called naked-eye planets. These include Mercury, Venus, Mars, Jupiter and Saturn. See the related link for more information.
No, due to the shape of the earth you can not see the North Star below the equator.
You would have to look through the earth to see it, earth is opaque.
It's the closest star because, It's the biggest star we can see, and the bigger it is the closer it is.
A star map for mars would be the same as a star map for Earth.