I have a moving mask but everytime I try to apply the effect on the mask, it just applies it to the whole clip even if I nest the mask
Copy the mask to the effect mask.
What do you mean exactly, I copied the clip with the mask and put it above the original. What do you mean by coping the mask to the effect mask?
Right under the effect line is a create ellipse button. Click that to make a mask. Then paste the mask into the Mask 1 line.
Hope this helps.
That didn't work for me, it didn't let me copy and paste a mask into the effect mask :(, sorry.
Select the moving mask you already made, the one under Opacity (make sure you have selected the title "Mask (1)" or whatever number you have) and copy it (I personally use the copy shortcut a couple of times to make sure it copied it, because sometimes Premiere gets a little picky with the copy/paste stuff).
Then select the title of the effect (again, make sure the title is selected) and paste it.
(Sorry if that's what you already did, but it's a very common mistake to have something else selected when copying/pasting).
When you add an effect, you'll see that in the Effects Controls panel, directly below the added effect's title, you have the three mask types available, those are the ones you need to use if you want that effect to apply only to a masked region; if you create a mask with the options under the Opacity title, the mask will determine what area of the clip will be visible, but whichever effect you add will affect the entire clip, regardless of that mask.