You can drag a hyperlink in both a dataview and a template grid. Only the attributes of the object of the dataview in which you are placing the external link widget can be used. I described two different kind of external link implementations:

Website link:

1. Add a website caption attribute
2. Add an URL attribute of type Sting to the same object
3. Add the external link widget in the dataview of the object
4. Connect the caption attribute by clicking the right mouse button on the external link
5. Connect the URL attribute by clicking the right mouse button on the external link
6. Add a microflow which is triggered on change of the caption attribute field and check whether the caption attribute already contains http:// or https://. If so, the URL attribute is exactly the same as the caption attribute. If not, set 'http://' + the caption attribute.

Email link:

1. Add a email caption attribute
2. Add an URL attribute of type Sting to the same object
3. Add the external link widget in the dataview of the object
4. Connect the caption attribute by clicking the right mouse button on the external link
5. Connect the URL attribute by clicking the right mouse button on the external link
6. Add a microflow which is triggered on change of the caption attribute field and set the URL attribute as 'mailto:' + the caption attribute.

I would also refer to this question.

If it is used within a dataview you can place the External Link in the form and then rightclick it to choose the caption and the website url as variable.