The trick with curry is to make it the day before. It's always better a day or two later because it gives the herbs and spices time to wander through the whole sauce.
Step 1: About Our Bastardized Brit-American Indian Food
Disabuse yourself that you'll ever make any of your favorite restaurant dishes at home. The fun of cooking is in chasing those tastes down. You won't find them all, but you'll know more than when you started and probably find something that'll be in your recipe card file for life.
Indian food commonly uses what we in America might think of as pie spices. Cinnamon, nutmeg, cardamom. The awakening American palate wouldn't have thought to put cinnamon on anything but buttered toast or in an apple pie fifteen years ago. Along with these you'll find those common equator spices: cumin, coriander (seed and leaf - cilantro), ginger, hot peppers, turmeric. And those versatile, ubiquitous alliums: onion and garlic.
That's pretty much all you need for most any curry (not all at once, but you could run across a recipe that does use all of them). A few specialty spices will have you ready for any curry you might encounter.:
Fenugreek (leaves), they will probably be called kasuri methi or just methi leaves
Spice blends like garam masala, chaat masala, tandoori masala, etc.
If you have these things around you're halfway to becoming a curry head.