How to factory reset an Apple MacBook?

I'd refer you to two support documents

What to do before you sell, give away, trade in, or recycle your Mac

and

Use Disk Utility to erase an Intel-based Mac (with a link to the silicon Mac equivalent page). Some would also reinstall the original operating system on a Mac.

Please help us help you. WHICH "Apple laptop???"

Apple has made notebook computers continuously since 1989 in easily up to a thousand variants. Reset instructions for one family of Apple notebooks may be harmful if applied to a different family of Apple notebooks.