Bible Discussion Thread

I am quite new to Bible reading so I have a few questions to ask. I am sorry if my questions seem naive to some people, but perhaps some kind person might help me out. Verse 3 - what was the source of the light since the Sun and the Moon and the stars were not created until verse 16? Did God ensure that the light shone on the Earth from one direction only so that night and day was created by the Earth spinning on its axis at the same rate that it spins today? Verse 11 - vegetation was created but would have required the Sun for photosynthesis. Did the light created in verse 3 also provide warmth which would also have been required? Verse 16 - before the Sun and the Moon were created, was the Earth floating about in the void not orbiting any other celestial body?
Thanks in advance to anyone who can answer me.