Welcome to Orchidboard!
Orchids aren't that difficult to keep and rebloom, once you learn the basics.
For the Phals, you can have a look at this great thread, it's full of useful information:
The Phal abuse ends here.
For your other 2 orchids, do you know what type of Dendrobium? (some labels with tell you if it's a Phal type or nobile type dendrobium). The care is really different between the two types in order to get the plant to rebloom. Phal type Dens do well with phal care, while Nobiles need a cool winter rest.
The Miltonia (probably a Miltoniopsis, also known as pansy orchids) will like cooler temperatures and more frequent watering that Phals.
Hope this helps you a bit, and don't hestitate to ask questions!