Hi guys.

I'm changing the footprint of the former owners.

Last night I change the floor mat into new genuine but found one of the hook from the driver side is missing.

found the one who sells this part but don't know how to install it.
Should if remove all the carpet and seat ?

Is there any easy way to put it?

 

They shove in through that one slot, eight bucks for two on Amazon.

Here's a picture of the retainer side:

 

Thanks Jay.

I've been looking for the clip for the installation.

Do you know how do to that?

is the only way to do is to remove the whole carpet and seat?

 

From the picture CeeJay posted, the clip is part of the hook. There may be a broken part of the old hook under the carpet, but I wouldn’t worry about looking for something that might not be there.
The new hook should have the clip as part of it. Simply push the toothed part of the clip through the slot in the carpet.