Question

write the step to filter email message from unknown/anonymous senders​

Answer 1

Steps to a filter email message from an unknown sender:

One can create a filter to stop getting emails from unknown or specific addresses.  

The easiest way to generate a filter is to put a check next to the message in your inbox, click the "More" drop-down menu and select "Filter messages like these.

“A filter menu will appear, even now set to catch all messages from that email address. Liable on the view you use, you may see a "Next Step" button; if so, click on it.  

The preceding thing you have to do is select the action the filter should take, and if you don't want to see emails from that address to any further extent, you can just click the "Delete it" option and then click on the "Create filter" button.

Hope it helped...