Short sentences are usually easier to understand.
And short sentences are more lively.

If you write a really long sentence containing lots of different ideas the reader has to wait until they reach the full stop before they can take a quick mental break to process all the ideas and all the things you have told them and then they have to make sense of it all and figure out how they should respond. (that sentence was longer than it needed to be – 61 words)

Joining words like ‘and’, ‘but’, ‘then’ are good places to consider breaking a long sentence into two or more sentences.

On average, aim for about 15-20 words per sentence. But don’t make all your sentences that long – readers like variety. There is nothing wrong with a 3 word sentence, and nothing wrong with a 35 word sentence. Just don’t write them all the time