So sorry about you desktop mate.
However, Adobe Lightroom is not big on photo manipulation and that can be done on Adobe Photoshop. Since your desktop is faulty I'll recommend you use Photopea its an only Photoshop web app just like the desktop software.

It is an editor on the go. Here is a screenshot of what it looks like

Almost exacly like the exe. files for desktop.

I hope this was helpful.