Shadowland41

I tried to install the SMAPI 2.6 beta because one of the mods that I installed said that I need to update the SMAPI, I downloaded and installed 2.6 and tried to run the game, but the text in the start up window said that I am running Stardew Valley 1.2.33 but I need at least version 1.3.23. So my question is, how do I update to the latest version of the game. I downloaded the game from Steam about two days ago and apparently downloaded the oldest version.