To activate a tool from the process explorer you can double click on the process icon /click on the launch process icon ( E ) or drag the icon to desktop and have it displayed there for easy use, you can select many like this and place them on your desktop for even easier use and access to your most used processes

A) Favorites--Shown at the top are usually your most used and Favorite processes

B) All processes--Lists all the processes

C) Selected processes highlighted in blue

D) Collapse or expands nodes i.e. controls menu display

E) Launch selected Process

F) Add selected process to your favorite list ( right click on process to remove from favorites)

G) Show extensions -- shows details on process

To close the panel you can click the standard controls at the top or any free area of the background