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You are dealing with a one piece crankset. This Park Tool video shows the viewer how to get this done. More common tools to assist in this job is an adjustable wrench ("crescent wrench" is a specific brand and type of adjustable wrench but that phrase has morphed into a synonym for adjustable wrench). A flat bladed screw driver. A hammer. Needle nose pliers. In the video, the gentleman uses a special bicycle wrench to remove that ring (it's a threaded cone nut). In your pic, you've got the hex lock nut loose. The keyed washer remains in place and partially covers this cone nut. Note the slots in this piece. You'll have to figure out a way to engage these slots so you can torque this piece loose and unthread it completely. You can use the screwdriver as a punch by positioning the blade in one of the slots and tangent to the ring. Use the hammer to tap on the screw driver's handle so that you can "break loose" the cone nut's threads. Once it breaks loose and starts to turn (to the RIGHT---see next sentence), you can come in with your needle nose pliers, engage both slots and continue to loosen until you can use your fingers to complete the removal. Try engaging the slots with the pliers and attempt removal first. These cone nuts aren't installed with a great amount of torquue, but time and corrosion may have frozen it in place and it may require a little "persuasion" to get moving. Make sure the keyed washer is off before all this. PLEASE NOTE: on this left side of the bike the pedal, locknut and and cone nut are LEFT HAND threads so to remove, one turns them CLOCKWISE.
In your question, your description of the pedal is a bit confusing. Typically the pedal will thread into a hole at the end of the crank arm. Often its a 1/2 inch spindle on these types of cranks but could be 9/16". (Metric equivalents are 13 and 15mm respectively). There are wrench flats on the end of the pedal spindle where it joins the crank. Sometimes the pedal is threaded and torqued tight by the use of a hex key placed in the hole found a the end of the pedal. If you dont see any wrench flats on the outside, look to the inside--the end of the pedal spindle where it comes thru the crank arm for this hex-key slot. Your pic just cuts off a view of this on your right pedal.