To start you need to read each plugin documentation.
I don’t know how buttons plugin works, but I imagine that you need to define a template or similar.
If not (a template), why type note(New Task) template? If you want a command maybe you need to write type command… I don’t know.
You can’t copy something from anywhere without understand how it works in that specific context. Imagine that it works together another plugin?
Btw class dataview-button isn’t directly related with dataview… I guess class is a CSS style thing, i.e. a defined class to style the button in some css snippet…
The problem is that you are telling the button to use a Template and carry out an action. I don’t think it will do both. I think the Template line is firing and that means that you don’t get the Tasks action.
I think you need to remove the line “type note(New Task) template”. That will allow the Tasks action to fire.
Check the Buttons documentation, as there are plenty of examples.