Here you can write more content that you might want as well as a n external link to [learn more] ((https://docs.microsoft.com/en-us/azure/). If you want to add a button to take them to another part of the portal, you can either take them to a create a resource such as: Create a resouce group
or opening a blade such as:
You may also want to add an image, which might be hosted on your github repo 
or you may want to put it in a storage account
