Under content,please select Browser Push Notification to access the bpn template gallery. Please click on the "create new template" . Please provide the details mentioned in below pics and click on "Create Template".
Image - 100 x 100 px, size less than 200kb
Title - 25 to 40 characters
Message text - 40 to 60 characters
Large image - 360 x 240px, size less than 240kb
Updated about a year ago