Yes. there are several opportunities to see your donation page in preview mode. Using either the Simple or Advanced page designer, a preview is available on the Preview/Publish tab.

Using the Simple page designer, you can also see a Preview via a link at the top of the Donation Page Settings tab. You can also see a preview on the Style Donation Page tab.

Using the Advanced page designer, you can see a preview of your page via the Page Preview link on the Page Designer tab.