The Parameters tab can be accessed by clicking on the button outlined in the image below. All Parameters in an Organization will be found here. There is also an option to search for and create a Parameter.

Click on a Parameter’s dropdown arrow as shown in the image below to expand and access these. The Parameters will be shown in the Solution they were created in unless created in a Global Solution.

The search bar can be used to search for specific Parameters as shown below.

Click on the button shown in the image below to create a Parameter.