To Add Custom Source Please Follow Below Steps.
Step 1: Click on Content Option in left menu [Folder Icon] and click on Sources
Step 2: Click on Add New Source
Step 3: Select Website in dropdown box which you want to add Custom Source
Step 4: Select Source Type
Step 4a: if you select "Defualt Feeds" you will get list of defualt 2500+ Sources
Step 4b: if you select "Custom URL" you will be able to add Custom RSS Feed URL
Step 5: Select Category and subcategory
Step 6: Select Autoupdate if you want data to be captured automatically
Step 7: Save
All the changes made by you will get reflected on website. if you face any issue please let us know.