Background isn't transparent in Blender?

Step 1: Click the "Render Properties"
image
Step 2: Find the “Film” tab
image
Step 3: Open the tab and click the “Transparent” button
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RENDERİNG
Press F12 button or click the render tab and click the "Render Image"

When your rendering is finished, you will see an image similar to the one in the photo.
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SAVİNG RENDER
Step 1:Open the Image tab


Step 2:Click the “Save As…” or use the shortcut “Shift+Alt+S” to Save As
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Step 3: Give a name for your image and click the "Save As Image"

You are done now.The result should be like in the picture