To change your shop’s name in PrestaShop, first open your site’s Admin Control Panel,
1. Go to Preferences>Contact
2. Replace ‘Shop Name’ text box with your desired shop name.
3. Scroll down and click Save.
Also in the same tab, you can fill your shop’s data, such as Shop E-mail, address, and your shop’s phone number.
For more information, please watch the video below:Prestashop 1.4.x. How to change store title ,