What is a one-sentence summary of the following article?
You can use any web browser on PC or Mac If you are not automatically signed in, click Sign In in the upper-right corner. Type the email address and password associated with your eBay account and click Sign In.  Alternatively, you can click Sign in with Facebook, or Sign in with Google to sign in with your Facebook or Google account. If you have two-factor authentication turned on, you may need to enter a 6-digit code sent to you via text message to log in. It's in the upper right corner of the eBay website. It's the third tab above your account summary page. It's in the sidebar menu to the left. It's the link at the bottom of the page.  This displays the "Manage Shipping settings" page. It's near the bottom of the "Manage Shipping settings" page.  The "Edit" link is on the right side of the page across from each option in the menu. You have the option to select domestic territories, entire continents, as well as P.O boxes. This saves your new shipping settings. Users located in the countries you blocked will no longer be able to buy from you or bid on your listings.

Summary:
Navigate to https://www.ebay.com using a web browser. Click Sign In. Sign in with your username and password. Click on My eBay. Click Account. Click Site Preferences. Scroll down and click Shipping Preferences. Click on Edit next to “Exclude shipping locations". Place a checkmark  next to the locations you want to block. Click on Save.