The present continuous (sometimes called the present progressive) tense in English is really easy to make and is the same for all verbs. We make it using the present simple of 'be' + verb-ing:
(Click here if you'd prefer to learn how to USE this tense)

Here is how we make the positive:

Positive                                           Positive Short Form
I am sleeping                                 I'm sleeping
you are sleeping                           you're sleeping
he is sleeping                                he's sleeping
she is sleeping                              she's sleeping
it is sleeping                                  it's sleeping
we are sleeping                            we're sleeping
they are sleeping                         they're sleeping

We can make the negative by adding 'not':

Negative                                        Negative Short Form
I am not sleeping                         I'm not sleeping
you are not playing                     you aren't playing
he is not reading                         he isn't reading
she is not working                      she isn't working
it is not raining                            it isn't raining
we are not cooking                     we aren't cooking
they are not listening                 they aren't listening


Questions are also really, really easy. Just like we made the question with 'be' in the present simple, here we also put 'am', 'is', or 'are' before the subject to make a 'yes / no' question:

Yes / No Questions
am I eating chocolate ?
are you studying now ?
is he working ?
is she doing her homework ?
is it raining ?
are we meeting at six ?
are they coming ?

​For 'wh' questions, just put the question word at the front:

Wh Questions
Why am I eating chocolate ?
What are you studying now ?
When is he working ?
What is she doing ?
Why is it raining ?
Who are we meeting ?
How are they travelling ?

Here are some exercises :
Positive and negative
Mixed exercises 1