With One Page Express, you can place a link on a button that will direct users to a certain section in your website.
In the Customizer, select the section you want the link to send users to, and copy the #section-name:
Then, go to the button you want to place the link on, and click on it to open the popup with customization options for that button:
Under link, fill in the blank space with the #section-name you’ve previously copied:
You can choose to open the link in the same tab, in a different tab or in a lightbox.
Click Apply Changes. Then, press Publish. You can check if the link sends correctly to the wanted section, in your page.