Please follow the below steps to correct the performance issue for Lightroom.
Go to Lightroom Preferences from the Edit menu
Click on Performance tab
Uncheck the Graphics Processor
then, Go to General tab
Uncheck the option " Show Add photo screen"
Show Left Panel Shortcut : F7
Show Right Panel Shortcut: F8
Let us know if that helps.
Thanks Mohit for your prompt answer. Your above instructions allowed me to access full screen and left and right panels. However, now I cannot shut down Lightroom and am also unable to use the tool that removes details, such as water droplets and stains, as the circle to locate the area to be removed is frozen. Can you help me with this?
Mohit, the tool box for the graduated filter does not appear when I click on the graduated filter icon.