If you are looking for an official certificate then there is no such thing that exists. So you should take up any Django Training Course or find out any offline Django course that is not recommended. However, I would suggest you learn it online. The reason why you should enroll in an online training course:-
You get a lot of time that can be spent to study more.
To access your course content you need not go anywhere you can access it from your home and from anywhere.
You get 24/7 support to solve your queries, which you can not get in offline training.
You can also avail of a 1:1 mentorship during the course; whereas in offline training, mostly, one trainer deals with the whole batch.
It looks like you are a beginner. So, first, watch the following video tutorial, to begin with, Django: