1. Go to Extend and install the Content translation module. It will prompt you to enable the Language modules to be installed, if they are not.
2. After the module is installed, go to Configuration and then to the Content language and translation page under the Regional and Language section.
3. Check the checkbox next to Content to expose settings for the current content types.
4. Enable the content translation for the Basic page and keep the provided default settings that enable translation for each field. Click on Save configuration:

5. Create a new Basic page node. We will create this in the site's default language.
6. When viewing the new node, click on the Translate tab. From the Spanish language row, click on Add to create a translated version of the node:

7. The content will be prepopulated with the default language's content. Replace the title and body with the translated text:

8. Click on Save and keep published (this translation) to save the new translation.