Using SPD I export the site page after that I try to import this page to another SPD solution that time I am getting this error.
import/export site pages in SharePoint Designer is applied only across site collections on the same farm.
In your case,
If you have one page, try to move the contents of this page manually, to your destination.
If there are multiple pages, try to perform import and export to the library via PowerShell. for more details check Export sites, lists, or document libraries in SharePoint 2013
- Develop your site page via visual studio so you can deploy it to another farm.
- Also, check this free tool SharePoint Content Deployment Wizard for moving the contents.