In English, it turns out that how a word is spelled has some confusing and often inconsistent rules with respect to how the word should sound. A notorious example of this incongruity is with the letters “ough”. It turns out that this can be pronounced in 9 different ways, as shown by these representative words: rough, plough, through, though, thought, thorough, cough, hiccough, and lough (ends in a “k” sound!).
You may have heard of the “long” and “short” vowels, perhaps in elementary school. These words aren’t that precise, because these phonemes aren’t always stated for a longer or shorter time. But it’s a quick way to remember 10 phonemes – the long and short versions of “a”, “e”, “i”, “o”, “u”. With respect to spelling, I did want to point out one surprising thing. In the American dialect, the “short o” phoneme (/ɑ/) does not involve rounding your lips. Say “top” or “box” out loud, and you’ll see what I mean. “Nacho” and “father” also use this, too. In British english, “top” and “box” use the rounded version of this phoneme: /ɒ/. It’s possible you’re slightly in between the two.