Downloads once (77 MB) and is saved in your browser.
Your browser asks for the microphone once.
Your audio stays on your device, nothing is uploaded.
Optional in settings: live text while speaking, and browser or desktop audio for meetings (Chrome, Edge, Opera).
Browser audio: pick a tab and tick "Share tab audio". Desktop audio: pick "Entire screen" and tick "Share system audio" (Windows, ChromeOS). Desktop includes the browser.