You can find the official builds for Mindustry through the following platforms:
Report: Free Download and Installation of Mindustry (v142) is an open-source factory-building game that is available for free across multiple platforms. While the Steam and iOS versions are paid to support the developer and provide integrated community features, the full game (including version 142 and newer) can be legally downloaded for free from several official sources. Official Free Download Sources You can find the official builds for Mindustry