How do I change number of products per row on desktop

Step: 1

In your shopify Admin panel, under THEMES & SETTINGS section in the left sidebar menu, click on the "Theme setting"

Like this:

Step: 2

After this, all theme settings page will appear. In the bottom left section "Product list" section available. In this section you can add or change how many numbers of products you wanna show per row on desktop

Like this:

Step: 3

Once you done with all settings, Click on the "Save settings" button.

Your settings will be saved successfully.

That's all done.