I've always had challenges with cooking rice from scratch. It seems to be rather particular, depending on where you live (climate, altitude) as well as the type of stove top you are cooking it on, and the type of pan you are cooking it in. At the very least, you should have a pan with a decent thickness for the base - nothing too thin - to distribute the heat evenly. The lid should also fit snug to trap in the moisture. I've also had much more luck cooking on a gas stove top where I can actually see the amount of heat hitting the pan, vs. an electric stove top, which is harder to gauge.
The basic technique is add the rice and water to a pot and bring to a boil, then immediately lower to a simmer and cover and let it cook to the specified time on the package. Often times, the directions will also say to let the rice rest, covered, off the heat after the cooking time, for an additional 10 minutes, before removing the lid and fluffing the rice with a fork.
You may need to do a few test batches to determine the correct amount of cooking time and liquid for where you live, and the type of stove you are cooking on.
For an easier time cooking rice, simply invest in an electric food steamer (my personal favorite, since it's multi functional and costs less than any decent rice cooker), or an actual rice cooker - but don't bother with the real cheap ones, they're just as tricky as cooking on a stove.
Another method you may want to try, is baking the rice in your oven. Again, the cooking times, and liquid amounts are trial and error. In my gas oven, I would use equal parts rice and water (usually a cup or two) in an 8" glass baking dish that came with a glass lid which fit snuggly (otherwise wrap it tightly in foil), then bake it in a non-preheated oven at 350 for about 35 minutes. The indirect heat will prevent scorching every time.