Welcome !
1- It depends
2- It depends. Some you can buy from Home Depot.
3- I think you can. But it is tropical plant might not grow in zone 6
4- There are rules. You need to study.

GENERAL:
You have to know what do you want to start from seed and grow.
Some seeds are much easier to germinate and some require special technique and way. Some need warm soil .... The same goes for seed sellers. Just do a google search.

I noticde that you are in zone 6. Probably your growing season is over now. For next year you can start from seeds maybe in February, 8 weeks before your last frost. This is for things like tomatoes, peppers, eggplant, NOT for things like cucumbers, melons etc. Most vegetable can be direct sown in the garden and there is no need to start them inside.

You need to study and educate yourself. Go to some other forums like: "Starting From seed" . There are numerous specialized forums here at GW that you can check and read. Also you can search in every forum or the whole GW site.

I have been in this and other forums for many years and still learning. So give yourself time and start with things that you know and like. Then find out how to grow them.

Hello Seysonn,

thank you very much for the detailed post. I have been checking other forums, blogs and books for more info. I also got tips from other members on this forum and I thank all of you.
I hope I get educated enough by Feb/Mar of next year, so I can start something for next year's garden.

thanks again.

I found that I usually planted my seed too deep. Most seed packs will tell you how deep to plant them. Then they have to be watered quite often. If they dry out they will die. I liked Miracle Gro seed starter mix the best of three different seed starter mixes I tried. You need to start them at the right time of year for your zone. I get my best information for growing at my local agricultural center or you can try Solutions for Your Life online.

Thanks all. I hope I did not forget to send you all a response directly by email. I appreciate the tips.

You need to check Planting Schedules in your zone

http://www.thevegetablegarden.info/resources/planting-schedules