Learn Arabic (Modern Standard): هي تفضل أن تشرب القهوة صباحا. - She prefers to drink coffee in the morning.

In Arabic, أن acts like the English word 'to', but it is always followed by a regular present tense verb that matches the subject. So literally, this sentence says 'She prefers that she drinks coffee'. Both verbs (تفضل and تشرب) must be conjugated for 'she'.

Does the word أن change how the verb تشرب is pronounced?

Yes! If you are pronouncing the short vowel endings, أن forces the present tense verb after it to end with an 'a' sound (fatha) instead of the usual 'u' sound (damma). So it is pronounced an tashraba instead of an tashrabu.

Why is there an extra alif at the end of صباحا (in the morning)?

That alif carries a double fatha (called tanween), making the '-an' sound at the end of صباحا (sabaahan). Arabic often uses this '-an' ending on time words to turn them into adverbs meaning 'in the [time]'. You could also say في الصباح (in the morning), but صباحا is a very common, single-word way to express it.

Do I need to include the word هي at the beginning if تفضل already means 'she prefers'?

No, you can drop هي and just start with تفضل. Including the pronoun هي is common for beginners to make the subject perfectly clear, but in Arabic, the verb's 'ta-' prefix already tells you 'she' is doing the action. Adding the pronoun here just adds a little emphasis.