Dynamic Tags Javascript

Hello,
I didn’t knew where to put this theme so I put it here because, well, I want to know “How To” 😀
Anyway, I’ve been searching a lot about this and couldn’t find a solution so I’m asking here, can anyone get me a instructions about how to create dynamic javascript <div> tag to WordPress site?
What I exactly need:
For example, one YouTube video has four parts, what I want to make is four numbers (1,2,3,4) inserted into theme so when visitor clicks number one it opens him Part 1, when visitor clicks number two it opens him Part 2 but at same post or page so he doesn’t have to wait for new page to load.
Reason why I’m asking can that code be embedded to theme is because:
For example, there are 5 YouTube videos with 4 parts. I would like for my site to have implemented that there is automatically sets four numbers (or more but in way that I can delete them) and then I just have to change embed code for each one of them.

I’m not sure did I explain it well, I have exact example on on site how that should look but I’m not sure if I can post link to that site here.

Thank You