How to justify text in wordpress Gutenberg Editor?

Step 1. Login to your WordPress Dashboard.

Step 2. In your Dashboard click on Appearance.

Step 3. Click On Customize.

Step 4. Now click on Additional Css or Custom Css.

Step 5. Write the following code in box.

p.justify{
text-align: justify;
}

Step 6. Now go to the post you want to justify and Select the paragraph click on block and select Advanced.

Step 7. Simply write justify then save and publish it.