Hello,
Sorry to say but right now for the Display Widget style of the Action after add to cart, there isn’t a Continue Shopping button available to show or add manually but you can select Show Popup style of Action after add to cart then in that it shows the Continue Shopping button already like it is depicted in the following GIF: https://woodmart.xtemos.com/theme-settings-tooltips/action-after-add-to-cart-show-popup.gif
To set this on your Site, you need to go to Theme Settings > Shop > under the Shopping Cart Widget, you will see Action after add to cart > there select Show Popup: https://snipboard.io/235UVs.jpg
Best Regards