Hi, I assume you’re playing the Tiny Life Demo (which is the only version of Tiny Life that can currently be downloaded), which doesn’t have support for mods. To be sure that this is the version you’re playing, you can go to the rightmost tab of the Options menu and either see a button to open the mods folder (in which case you’re playing the now unavailable public beta, and the folder to put mods in will open automatically when pressing the button), or the information that mods are not available in the demo.
For more info about the Tiny Life Demo, you can check out this devlog post.