Whisper is open source and free AI model for transcription. If you’re not comfortable setting it up Audacity has a whisper plugin you can easily add and use.

As to how good it is, it really varies a lot but it is free. You need another plugin to export to a subtitle file.

Edit: Actually the program Subtitleedit (https://www.nikse.dk/) has the ability to run whisper models and you can download them from within the app, also no need for another plug to export so that’s probably the easiest. Once it’s as text you can use the translate menu within SE to translate. You need an API key (paid) for most of the truly good services but you can use basic google translate for free and it should give you the gist of things.