Where can you get some pre-sown orchid seeds?
The link below is a good starting point. You will have to do your own research since it is not clear what you are interested in and there are about 30k orchid species and uncountable hybrids.
Seedlings in flask just need correct temperature, light level (fairly low light for most) and day length. The flask supplier may indicate what conditions are required especially light level and temp. However, you should do your research to make sure you see all of the alternatives.
Since the flasks are sealed and are only opened when it is time to transplant the seedlings the care of seedlings in flask is minimal until time to remove them.
Just to give an example, I visited an Orchid nursery in Fla and they kept about 40 flasks of seedlings on a rack in the main office. Right light and temp and the staff were could easily inspect the flasks every day.
http://www.orchidmall.com/supplies.htm - this page includes a dozen or so Orchid flasking services.
This YT video is pretty good on flasking -
Do a search for Orchids on YT and you will get a weeks worth of mostly good stuff about growing Orchids.
I warn you, Orchids are addictive. I once had a collection of over 100 plants. I stopped at 100 because I had no more room. At the time I would have just kept collecting until there were no more plants to collect.