Present Simple Tense

When do we use present simple tense?

Use 1

Actions that are done habitually.

Ex. He wakes up at 630 am every morning.

Use 2

It is factual, or it is true.

Ex. The world is round.

How to form present simple negative sentences.

Use 1

Just add does + not between the subject and the verb

Ex.  He doesn't wake up at 630 am.

Use 2

Add is not between the subject and the verb

Ex. The world isn't round.