If you're using a work computer, I strongly advise not putting that on there, especially if it requires installation. At my work, we regularly scan for apps like these, as well as the physical jigglers that connect via USB. We do this for security reasons primarily. There are several built-in ways in Windows to simulate activity, I really don't see the point in downloading random apps from potentially sketchy sources.
One example off the top of my head: If you have multiple monitors, go into presentation mode with PowerPoint on one of them. This way, you can still have one monitor available to see your email and whatever chat app your org uses. If you have just one monitor, pretty sure you can still push it to the back or minimize it and it'll still work. Also, watching videos within SharePoint is another way of preventing Windows from detecting inactivity. If you use Teams, you can start a meeting with yourself (though, some orgs monitor activity on Teams, so use this at your own risk). If PowerShell isn't disabled, there's also options there.