To get legally for free, you have three primary options:
The modding community (tModLoader) stabilized on 1.4.4.9. If you want to play the legendary or Thorium Mod in co-op, you need this version. Newer versions break mods for months. Terraria Free Download -V1.4.4.9 CO-OP-
The specific search for is not random. This version number corresponds to the tail end of the "Labor of Love" update (version 1.4.4), which was released in late 2022 and patched throughout 2023. To get legally for free, you have three