The easiest way to get 3.74 is through the Vita's built-in update tool: Connect your Vita to Wi-Fi. System Update Update Using Wi-Fi
The PlayStation Vita, or PS Vita, was a beloved handheld game console released by Sony in 2011. Despite its impressive hardware and innovative features, the console ultimately failed to gain significant market traction, leading to its discontinuation in 2019. However, the PS Vita still maintains a dedicated fan base, and many users continue to enjoy its extensive library of games. ps vita 374 firmware link