Hello,
Thank you very much for choosing our theme and for contacting us.
You can find and configure the actions after adding to the cart in the Theme Settigns > Action after adding to the cart.
You can set the popup window or sliding sidebar.
In addition, you need to configure the shopping cart in the Header builder:
Please navigate to Woodmart > Header builder http://prntscr.com/iyd2pe
Choose the proper header type (your current) http://prntscr.com/iyd333
Modify the shopping cart http://prntscr.com/iyd3h3
Take into consideration that there is also the mobile view of your header http://prntscr.com/iyd3v3 check all the elements there.
Please note, the shopping cart form in the Header builder should be the same: sidebar or drop-down in both: mobile and desktop.
Best Regards