@bastienchill: Hello there,
You can use our plugin Generate Child Theme to create child theme.
Install and Activate the plugin
Then,
Go to => Dashboard => Generate Child Theme => Select Parent Theme as Bold Photography Pro and fill in remaining fields and Click on Generate.
This will create and activate the child theme.
Now,
Copy the folder template-parts/recent-posts from your parent theme folder to the child theme folder.
Make sure the path of the folder recent-posts in your child theme if the same as in the parent theme.
The path should be child-theme-folder/template-parts/recent-posts.
Now,
Edit the file front-recent-posts.php in recent-posts folder.
Search for the text More Posts
and replace it with your required text.
Let me know if this works out!
Kind Regards,
Skandha