On a Windows desktop or laptop computer, click the “Start” button, type “system information,” and select the result. On a Mac, click the Apple icon in the top-left corner, then select “About This Mac.” Mobile devices vary, but system information is typically found in the device settings.
Find and click on the "About" for your browser, which can generally be found by clicking on the browser name in the menu bar.
You can also go to one of the websites that detects and displays information about your device and browser, such as whatsmybrowser.org.