Moving Large Number of WordPress posts from One wordpress site to another existing wordpress site

In the WordPress admin of the new site, go to Below Steps
For Export Steps

  1. Tools>Export(Choose What to export).

Click “Download Export File” and save the file.

  1. Tools>Import.
  2. Select “WordPress“, install the importer by clicking “Install” in the popup, and “Activate Plugin & Run Importer“.
  3. select the file to upload (the one you just downloaded). Click “Upload file and import“