Hello, I'm taking a break from my main project and would like to start a new maybe easier project which is changing the animation from a base games interaction, is there a tutorial on how to do that? also where can i find the specific the interaction?

Maybe there could be a better solution, but you could create a new class and copy the interaction you want to change, keep all the values as default (if you want) and just edit the Run method to replace the animations. Then in OnPreload() add your replaced interaction for example like this:
AcademicBusinessPlanner.UseBusinessPlanner.Singleton = new BusinessPlanningInteraction.Definition(); (credits to Code of Cave Snippets here for that).
But if you do that, you'd need to create a tuning file for the new interaction. I am not familiar with any way of replacing animations aside from editing the Run() method.

Fair warning, I have very little experience when it comes to replacing animations, but hopefully this info can at least get you on the right track.

To change an interaction animation, you’ll have to find the correct Jazz file first. Start by opening the main Jazz file with S3PE (C:\Program Files (x86)\Electronic Arts\The Sims 3\Game\Bin\Jazz\Jazz). Most of the jazz files are labeled, so look for the one that mentions the interaction you’re looking to change the animation for and export the file to a package file. Then open the file you exported in SmoothJazz and look at the animation names listed. Change the existing animation name to the animation name you want to be used (be careful to follow the correct formatting) and save the Jazz file. Then from there you should be able to import the edited Jazz file into a new package file, save, and place it in your mods folder (probably in Overrides).

If you need to find the animation name to replace the existing animation name with (assuming you’re wanting to use an existing EA animation), open the GameplayData file with S3PE (C:\Program Files (x86)\Electronic Arts\The Sims 3\Game\Bin\Gameplay\GameplayData.package). All of the EA animation names should be in there.

Hmm, for the little i know maybe that could work....

This seems like it would do the thick! All i need to know now is how to find the code needed for the interaction I'm trying to edit, as i said it already exists in game.

I guess it depends on whether you want to change *all* situations where an animation is used or only in one specific interaction. If you want to replace the animation period, @twinsimming's is the way to go, if only for one interaction, then you can do it my way. Note though jazz scripting is done pretty differently than c# modding but if you can find the jazz for your animation sequence, it *should* be pretty understandable how to add your own anim.