single.php probs

I’m trying to build 2 loops on my page. The index.php only features one loop and includes all the titles of the different posts. But then i want to be able to click a title to open a new page, which features the complete post (in other words single.php) but on the left side of that page, there should still be all the titles from all the posts, so ppl don’t always have to go back to index.php