Can you assign a sidebar to a specific page?
If you wish to add your sidebar to a specific page or post, just navigate to the page/post in question (or go to Pages/Posts >> Add New). Once you find the page or post you're looking for, open the Sidebars dropdown on the right side of your screen.
How do I add a dynamic sidebar in WordPress?
For this tutorial, let's add something simple. Drag and drop the “Calendar” widget into the new sidebar. When it comes to widgets and sidebars, WordPress will automatically save when you drag and drop a new component. It's when you make adjustments to the widgets that you have to click the save button on them.