You mention SIM jacking, but I see other comments here recommending Authy here, which requires a cell phone number and SMS OTP to set it up. Your second edit al

You mention SIM jacking, but I see other comments here recommending Authy here, which requires a cell phone number and SMS OTP to set it up. Your second edit also says you're going with Authy. That doesn't make sense to me. With any of these apps, you need to backup the first time setup code (or the QR code) for each site or platform where you're configuring 2FA. That's how you get the ability to set those up in another app if you lose your device. If you're on iOS, the latest iOS version (iOS 15) has in-built support to generate and populate two factor codes. If you'd like a separate app, I'd recommend OTPAuth if you're on iOS/watchOS/macOS (the Mac app is a paid one, the rest are free and allow iCloud syncing).