I'd suggest looking into apps like MangaToon or Manta. They sometimes offer free access to manhwa. Just make sure to check their terms and conditions for any restrictions.
You could find it on specialized manhwa apps or websites. Sometimes, certain fan forums or communities might have links or recommendations for where to read it. Just be cautious of the legality and reliability of the sources.
You might want to check out Manga Rock. It has a decent collection of manhwa, and there's a chance you'll find some free ones. Just be aware that the legality of certain sources on such apps can be questionable.