Render is taking way too much time

Hello,

I wanted to edit three 4k videos and i could not play them cuz i had red line above my timeline.
I started a render (so i could play videos in real time) and it was taking few hours per clip, let's say it needed 6 hours total but i was in a hury and i quit at 50% thinking i could find better & quicker way.

I decided i will search for best render preview options and start a render again, it is taking impossibly long time to do so. For 8 hours it has rendered 12.00%. With better settings, cleaned cach, more RAM memory that premier can use.... and it went wrong.

Please write what do you know about render and time, estimated time left 63 hours i a pure hell.

I dont have this much time since the project has to be launched, please help. (I am already late).