On my website I have photo wallpapers. I want to optimize this page for search engines. There is one main page where all of this photos are listed. On this main page I use keywords like "photo", "free photo", and "wallpaper" in the title, h1, descriptions, and text.
When user clicks on some photo, it opens in second page with the same keywords. I'm not sure if it is good for rankings when I use the same keywords on other pages.
On this second page, should I use meta tag with rel='canonical' for better SEO?