wow so many questions and possible answers. lets keep it short.
- size & space of where you are
- budget
you can do soil-less, soil, hydro (DWC, Ebb&Flow, etc) - its all kinda how much space do you have (along with other stuff like time, $, etc.)
you dont flip over to flower/bloom cycle till the plants are usually 2+ wks into veg. That's ideal. I try to do at least 3 - 4 wks. It depends heavily also on size/space. you veg longer, you get bigger, bushier plants. There are techniques to combat that - but thats neither here nor there for right now. RIU search on topping, LST, pruning, etc.
they will come to you already in a grodan cube most likely, and they should have very visible roots on the bottom - ideally. Its not like you cant put them under a T5 floro if they dont have roots - but more roots the better, if you have a chance to look at the clones before you buy them.
they need light, but not HID lighting right off the bat. You could do like 400w MH, raised way up; some will suggest maybe a mix of CFL and/or floros for early on, like the 1st few days you have the clones. I personally just get them into the medium asap if they are well rooted. I did get some not long ago that had to be put under domes (cus they had like no roots showing) and under a T5 like i mentioned. did that for about 10 - 12 days, got good roots then transplanted.
depending again on size/space, if you transplant them to say a 1 or 2 quart container, give them maybe 14 - 16 days to get healthy root system going, and then pot-up to your final container size, say, e.g. 1 gal or 2gal. container size will vary on your needs.
get some mycrorhiza (spelling off) to put in the transplant areas to help build beneficial bacteria/organism colonies. compost tea is a great thing too to give them during this stage.
i'm new to coco, but have some soil experience. I personally think coco is the jam right now. very forgiving medium, easy to work with, is free from certain issues that can plague soil grows (soil based diseases), retains water well, etc. If you can get some 100% coco near you, I would go that route. Everyone has their own opinion, style, preferences, etc.
