I'm curious to know what word you can't make the sound of!
It seems to me like you want to use pronounce here. If you can't physically create the sounds of the word because it's too complex or foreign to your native language, that means you are having trouble pronouncing the word. You can also use saying the word, but say is such a general verb with a wide variety of meanings. It's probably more precise to use pronounce in this situation.
I wouldn't use read here, because there are many very difficult words that can be read but not pronounced well. An exception to this would be to read aloud, which means to speak the words as you read them. So you could say something like:
I am having trouble reading the words aloud.