I would recommend web development. More specifically WordPress setup. WordPress is very simple and there are thousands of themes available to suit any business. It is a blogging platform but I see so many businesses using WordPress as their main website. You simply guide businesses through setup process help them choose a theme & train them on how to use it.
As you get comfortable with WordPress, you can start customizing themes, or even writing complex plugins.Then slowly you can add more offering such as setting up Shopify, etc.
The best part about this business model is that other than minor hand holding you don't have to provide any time consuming technical support for the customer. If their website is down, they contact WordPress or Shopify etc.