The easiest way to play Lc0 if you don’t want to install it on your computer is to use one of Lichess bots.
You can find them in the respective lichess team.
The ones that are almost always online are Lc0Test, leela2200 or MiniHuman.
There is also an official Leela bot called LeelaChess, but most of the time it’s offline.
The Maia bots run on lc0 networks as well, you can play them on lichess.