Save PDFs and images in Preview on Mac
Preview automatically saves changes for you as you work, but you can also save a document manually. When you edit a file, Preview saves a version at least every hour (more often if you’re making significant changes). Preview also saves a version when you open a document, save or duplicate a document, lock or rename a document, or revert to a previous version.
Go to the Preview app
on your Mac.Choose File > Save.
To save a file using a different filename, press and hold the Option key, choose File > Save As, then enter a name. Choose where you want to save the file, select a file format, then click Save.
You can also save the document with a new filename or change its location. Hold the pointer over the document title and click 
on the right.