My catalogue wont open

So what is your OS (Mac or Windows)? What is the name (Mac) or drive letter (Windows) of the external drive? What is the file name of one of these images?

i tried to create a new catalogue to see if it was possible to import new photo but it's not working, the problem still there, there a ! on the new files 

when i realize that it still work out well with my imac i deinstall and reinstall lightroom on my laptop thinking there was maybe a problem with the application but the problem still there 

yes

Did you use Lightroom to move the files?

It was working perfectly well on both my computer but yesterday i moved some pictures between 2 files on my laptop (macbook) and boom, everything was mark with a ! but only on my laptop, not my imac 

I suspect that the external hard drive has a different name or drive letter when connected to the laptop. Check to ensure that the drive letter or name is the same or in the library module right-click on the topmost folder and choose the option to find missing folders or update the folder location and choose the appropriate folder on the laptop that points to the external hard drive.

If you use Windows, then the same drive could have different drive letters on both computers.

My image files are on an external hard drive. I'm using the same for both my computer

I assume you are referring to Lightroom Classic. Are the image files on the laptop? Is Lightroom looking for the image files in the same location (same drive name or drive letter) as on the other computer?