There are vowels and consonants all represented by letters. Usually, each letter represents one sound in a word, but there are some exceptions like "th", "sh", "ch", "dg", and vowel combinations "ou", "ea", "ei", etc. It's kind of a complicated question, because it's hard to understand what you mean. But don't let jerks like Eliot make you feel self-conscious. Whether or not you capitalize the first word of your sentences means absolutely nothing and he's an old fogey.

The main principle is you put letters of the alphabet into groups, and you have words. Doesn't the "shift" key work on you PC?