How to add session cookie in weevely?

I am pentesting a website and I was successful in uploading a php backdoor and finding the path of the backdoor. The only issue is that in order to gain access to the uploaded file I need to be logged in with my account. i can do this by adding my session cookies in weevely but how can I add my session cookies in weevely to access the backdoor file? Is there a way to do this or is it possible?