you dont have to start them indoors but you usually have alot better germination to seedling rate indoors where temperatures and environment can be controlled as seedlings like high humidity and warmer growing meduim temps of 70- 85 degrees, but it can be done outdoors just not something you will porobably want to try with purchased seeds but if you are just using bagseed and you have plenty to use there is no reason you cant start them outdoors.
as per lights flouros or cfl work ok if kept close if you have a hid available from growing indoors you can use that also.