English has a stress based pronunciation which means that intonation and stress of key words is the most important factor in order to be understood.
Spanish has a syllable based pronunciation which means that intonation is relatively less important and we should focus in the separate emphasis of the syllables.
For example: CASA (house) is made of two sounds CA + SA
while CASO (case) is made of sounds CA + SO
Both syllables should be pronounced separate so we can tell if the speaker is talking about a “house” or a “case”.
The differentiation of the sounds of the Alphabet is key, of course. You may watch a video with the sounds of Spanish letters here
Whenever you are reading in Spanish try to separate syllables when pronouncing and don’t be afraid to slow down and read at your own pace. That will help you achieve a great pronunciation and a very effective communication in Spanish!