I need help! this does not appear to be a sketchup model

There’s nothing to recover in your file. It’s about 99.9% filled with zeroes.

Where have you been saving the file while working on it? Have you tried renaming the .skb backup file and opening that?

I saved my work in SSD External. I tried it but it’s still the same.

Saving to external drives, especially when the file is as large as yours seems to be a common cause of file corruption. Best practice is to save to an internal drive instead. Then copy the file to the external drive if needed. Also make sure you are keeping your file cleaned up. At 662 Mb I expect there was a fair amount of unused content that could have been purged. At least that is another common thing with huge files.

I would suggest in addition to saving on the internal drive, that you take advantage of the Trimble Connect storage included with your Pro subscription and save your file there also.

Unfortunately then there’s nothing for it but to start over.