You can view your spam email folders in the left side panel. This shows the spam folders for the 'Favorites' accounts. View. You can choose to view other folders, including other account spam folders, using 'Folder Filters' View

When you see an email in your spam folder that is not spam, swipe and move the email to the inbox or choose 'Not spam' in the swipe actions. This will move all emails from the same sender into the inbox. This action will also add the sender to the 'Spam Safe List' so their emails won't be marked as spam in the future.

There is a spam block list for managing spam email addresses. Tap on the block list link inside the spam rule. You can also open the app settings (View) - Spam - Spam Block List. You can add or remove addresses.
When you swipe an email as spam, the sender address will be added to the Spam Block List so any more spam emails from this sender will be removed automatically in the spam rule, (if the rule is enabled).

You can edit the spam safe list. Open the app settings (View) - Email Management - Spam Safe List.