Present Simple and Present Continuous.
Watch one of the following YouTube movies. The first video is longer but contains much more precise information. The second one gives a very brief summary.
https://www.youtube.com/watch?v=VP8MRGAjgAs
https://www.youtube.com/watch?v=1ShOoOd3FAo
When you have understood well how and when to use the Present Simple and the Present Continuous, go to Studiemeter. Of course, for this exercise, you need an account on 'Studiemeter'.
Studiemeter
When you are logged in, go to FACE and then to the exercise 'tegenwoordige tijd & nu aan de gang B1'. Do the exercise.