To put GIFs in the WhatsApp status, we have two options: using our image gallery or using an application.
Set GIFs as WhatsApp status from the gallery
To use this method, you must first have the GIF you want to put on your phone. Knowing this, open WhatsApp and tap on the Status tab:

Then, click on My status to add one:

The camera application will open. Slide your finger up to open the gallery:

From the gallery, select the GIF:

Tap on it and then on the send button to put it in your status:

When you have done so, it will be set in your status:

Setting a WhatsApp Status GIF with an Application
In this case, we are going to use the app from the most popular GIF repository on the Internet, which is no other than Giphy, and that you can download here below.
When you have installed it, open it and you will find this on the screen:

You can choose a GIF from those displayed on the main screen, but you can also use the second button on the left at the bottom of the screen to explore the latest trends or GIFs by category:

Additionally, you can always use the search bar on the home page to find the one that interests you most:

In any case, when you have found the GIF you are interested in, tap on it to open it. You will see it at a larger size, and you will also see a button shaped like a paper airplane. Tap on it:

Now, the options for sharing will appear. Of all the ones offered, we tap on WhatsApp:

In the next menu, tap on My status and then on the green button:

On the editing screen, we tap on the Send button:

We make sure it has been set in our WhatsApp status:

Set a GIF as a WhatsApp status with the internal camera
This is as simple as opening WhatsApp, going to the Status tab, and tapping on My Status:

The device camera will activate. We will have to tap and hold the button used to take pictures so that it starts recording a video:

Now, we can record whatever we want with our camera, but for no longer than five seconds. When we are done, we will see this on the device camera:

With the sliders at the top, we can adjust the duration of the clip, and to the right, we can select that the video plays as a GIF. When we have set the duration of the GIF, we tap on the Send button:

And now, we make sure it has been set in our status:

And that is it, if you follow the steps showed in both methods, you will see how easy it is to complete this task.