What is the best way to optimize images?

Question

Server optimization

On the site, which is running CMS Wordpress, the client uploaded a lot of photos larger than 2Mb. These photos on the inner pages are uploaded to the slider, 6 pieces each. Well, as you might guess, the pages with photos open in minutes. Photos are uploaded to the page via Advanced Custom Field (<? the_field('photoX');?>) - WP Thumbnails won't help. Filled with 200 pages, so manually not an option to do anything.
How can images be reduced?

Answer 1

Register the thumbnail size you need, then regenerate the thumbnails. Then run image optimization with any plugin. In ACF, picture fields must return an image object , not a link. This object will include the new preview size. You need to display it on the page.
Actually, about previews and regeneration, for example, here or here . We already wrote about optimization.

Answer 2

If I understood you correctly, then you need this plugin https://wordpress.org/plugins/ewww-image-optimizer/

Answer 3

can come in handy - FileOptimizer I use this software, it presses perfectly