so question in when user open this page server must handle 'get query' + 2 queries for css + 2 queries to js + 35 queries to load images so we have 40 queries which we need to load a page?
Yes. However note that with proper configuration of your web server, subsequent hits from the same browser will be cached.
So if we have another server for images, the main server could process more users which open web site?
Generally, yes. Moving images to a separate host is a popular way to distribute load. Note that if you're not actually experiencing problems right now, then it's probably too early to worry about how you're going to implement a solution, especially if your content is all static files.