Rather than re-type all the basic info over again I hope you don't mind if I first refer you to the FAQs here.

I'm new to growing from seed, how do I get started?

Ok, my seedlings are growing. Now what do i do?

How do I determine when to start my seeds?

Are the ones to start with. I linked the rest below. You also need to provide us with your location and growing zone with your posts - there is a box on each post to include that important info.

Can you use tomato seeds?

What kind of seeds? Packages of seeds from seed sellers? Of course. From store bought tomatoes? They are hybrids and usually don't breed true. From your own saved seeds? It depends on if they were hybrids or open-pollinated varieties.

Hope this helps you get started.

Dave

PS: Here are a bunch of previous discussions with those new to growing from seed with much more info too.

Here is a link that might be useful: Growing from Seed FAQs