How to change the shop grid?

Step 1:

Navigate to Options > Shop > Shop Layout.

Step 2:

If you want to display one product per row on the shop page, click on the left thumbnail next to the shop grid showing one vertical line.

If you want to display two products per row on the shop page, click on the middle thumbnail next to the shop grid showing two vertical lines.

If you want to display three products per row on the shop page, click on the right thumbnail next to the shop grid showing three vertical lines.

Step 3:

Click on save button.