It looks like this

Youtube video

How to install

KDE Store

It can be installed through the desktop settings.

KDE Store plugin link

Manually

1. Download and copy snow folder into your home plasma wallpapers.

wget https://github.com/IvanSafonov/plasma-wallpaper-snow/archive/refs/heads/master.zip
unzip ./master.zip
mkdir -p ~/.local/share/plasma/wallpapers/
cp -r ./plasma-wallpaper-snow-master/snow ~/.local/share/plasma/wallpapers/org.kde.snow

2. Open desktop and wallpaper settings and select the new wallpaper type Snow. If the settings were open already, you will need to close it first.