You have a couple curl types but it appears looser on the back sides and tighter in some areas and even straight in other areas.
You might want to first decide the style you want to wear it in and go from there.
I would recommend trying a full curly top and low tapered around the edges.
Have your barber taper your low sides and don't cut any on top.
To style the top just dampen it with your wet hands and then "scrub and mash" in your gel or conditioner just on the ends of each hair. Add more product and water (just to the ends) so it can clump and curl up.
The reason you don't want to add product to the hair close to the scalp is because you will want to have a fuller curl style that doesn't look too thin or matted down. But definitely use lots of product on the ends of your hair all over.
If you are going to grow your hair long, real long, then learn about natural care products but if you just want good looking hair then use products that help you achieve the look instead of being too concerned with healthy hair for growing out.
Just a guy with long curly hair