I'm unable to set the f-stop and depth of field of the viewport using Eevee renderer I've been using 3D programs for 15 years and this is a little nuts. I just want to make the viewport not blurry  I should be able to select the viewport camera like you can in Maya   and adjust the depth of field the f-stop the blooming and depth of field   , also I don't even know how to look through cameras I don't know how to change them or move them or really how to create a new camera it's extremely frustrating having spent two hours already just trying to create a new camera and make the viewport match what I'm seeing in the camera and vice versa
You can enable or disable the Depth of Field in Viewport Shading by going into the Viewport Shading settings. Click on the down facing arrow button on the right of all the shading styles in the top right of the screen. The Depth Of Field settings is at the bottom of the settings.