On WordPress.com, you can create your blogs and website easily. You don't need to worry about hosting and managing your WordPress website on WordPress.com when it is in simple or basic form. But, if you want to use different plugins and customize the website as per your requirement, you might need to move your WordPress website to third-party hosting.
Migrating your blogs from WordPress.com to self-hosted WordPress is an easy task that can be done by following the steps listed in this article below.
Please note that you may not find the same WordPress theme for the website created at WordPress.com, but you can choose a theme that looks close to the existing one. Also, you can install the plugins that you have on WordPress.com. You will likely see the jetpack plugin at a free-based website on WordPress.com.
Steps to Migrate blogs/ posts from WordPress.com to self-hosted WordPress –
- Ensure that your website is set to Public – Click on My Site >> Settings >> Privacy, and select Public.
- Click on the Save Settings button.
This allows permissions to import/ export your WordPress site and the media added to your website.
3. Now, export the existing website – Go to Tools >> Click on Export all.
Once you click the Export all button, it will give your registered email account the download link.
Suppose you want to migrate your WordPress pages in parts; you can select the option to export the specific content. For example, you can choose the WordPress post based on the author, status, start date/ end date, categories, etc. This option can be helpful when you have many blogs and pages on your website, and they may give you an error while migrating because of the large amount of data/ large file size.
After clicking on the download option received in your email, you will see a zip containing an XML file downloaded to your local system. 
4. Log in to your self-hosted WordPress admin panel.
You should install the plugins and themes on WordPress.com for the best result.
5. Change the permalink structure to the day and name that match the default permalink structure on WordPress.com. 
6. In the next step, we will import the content.
Click on Tools > Import >> Run Importer.
If the Importer is not installed, you can install it with a simple click.
7. Choose your XML file and click on the Upload file and import button. 
8. You will be asked to Assign Authors at the Import WordPress step.
You can assign the post to the WordPress admin or type the author's name here. However, you have multiple blog authors; you don't need to select anything. It will add the existing user with the correct permission. If you choose a user here, it overrides all the existing authors.
9. Then click on the Submit button. 
10. Here, you might face an issue with an error message, "This does not appear to be a WXR file, missing/invalid WXR version number."
To overcome this issue, open your XML file and change the WXR version from 1.2 to 1.1 to fix the issue. 
<wp:wxr_version>1.2</wp:wxr_version> to
<wp:wxr_version>1.1</wp:wxr_version>
11. If the website is imported successfully, you will see the message shown below -
12. Now, go to the post and verify that all blogs/ posts are migrated successfully.
13. Go to the media library and verify that all the media are imported.
You need to create a menu and widget that you have at Wordpress.com. That can't be exported. Also, verify that all images are loading from your media library, not Wordpress.com. If any of the images are loading from Wordpress.com, you must click on the images and upload them from the media library.
14. All the content is now imported; you can change the nameserver of your domain to point to the self-hosted wordpress. How to change the nameserver at various domain providers?