This video explains the difference between temporary and permanent domain forwarding with a demo on GoDaddy.
If you are building your website, then choose temporary. If you already have everything finished on your website builder ready for the world to see then select permanent forwarding.
So as long as you are working on your website, choose temporary. Once you are finished creating your website, change the setting to permanent.
Note: there is an option to choose to forward with "masking" which I explain in a separate video.