@aimen01 if you want you could configure the blog/archive page to not display thumbnail image, only show the thumbnail image for the top first (most recent or sticky post).
But I wouldn’t worry about it, also as mentioned in earlier post, in this particular case I would use bigger image dimension (like 900px, not some 300px) in the post content.
Your site is a blog. Of course, there will be many images on the blog or archive page listing 10 posts or so, plus the images in the sidebar. This is why Google suggests to reduce number of images because they require http requests.
But consider some web sites that has 5 big hero images in front page slider, or one that has big feature image in the header, those will weight more and have more page load time than your site.
Average Page Weights Increase by 32% in 2013
https://www.sitepoint.com/average-page-weights-increase-32-2013/
Average Page Weight Increases 15% in 2014
https://www.sitepoint.com/average-page-weight-increases-15-2014/