There are many lightweight Linux distributions on the market ... Unlike most modern operating systems, WattOS (and LXDE) doesn't include a System Settings or Control Panel app.

LXDE, LXQt, or XFCE for a Windows-inspired UI. Even if you can’t get the wholesale Windows experience, picking the right ...

A key difference from LXDE is that LXQt uses the Qt toolkit ... though you can install bare-bones versions depending on the Linux distribution and package manager you're using.