What are the easiest Orchids to grow in home garden??
Yellow Lady slipper or the Green orchid that came over from Europe (seeds itself in my garden). They are both terestrial and the yellow is native to Northern North America.
I wouldn't recommend Cypripediums, since they require different care based on the species and generally like light, humus-rich, well draining and acidic soil, which is very hard to achieve and maintain in a garden. If you want cold-hardy orchids, try Bletilla striata. If you have a mild winter, Calanthe or Pleione may work, as they don't require that much soil amendments or extra care. If you can create a proper mix and get a native Cypripedium, it might be worth it, but I wouldn't recommend them for a beginner. If by Home garden you mean indoor garden, then Phalaenopsis, Oncidiums and if you have the light, Cattleyas might work for you. Read up on the care ; lot of the information you get from the tags is horribly wrong (water with ice cubes...repot in moss). Ludisia discolor might do well since it grows in soil and low light.
Typically they are only grown in green houses. Remember they are tropical plants so unless you live in a tropical region, you can have problems.