Adding jpegtran optipng and gifsicle

I am building a web site with WP, and trying to use EWWW Image Optimizer. After install, I get the message that I do not have jpegtran optipng and gifsicle installed

I am not very good at this, and struggle every step of the way, understanding that I am way out of me element, but very much wanting to learn

Does anyone know of a place offering very simple, very complete instructions as to how exactly to install these three tools in to my wp-content/ewww folder correctly ?

Thanks