How to watch bigg boss ott without subscription?

You've actually got a great option here. Bigg Boss OTT streams for free on the JioCinema platform in India. You don't need a paid subscription at all. The show is ad-supported, which is how they make it available to everyone without a fee.

Now, the main hurdle for anyone in the US is the geo-restriction. JioCinema is only available within India. Your most reliable and legitimate workaround is using a quality VPN service. Just set your virtual location to an Indian server, and you should be able to create an account and watch. I'd strongly advise against searching for unofficial streaming sites. They are often poor quality, full of pop-ups, and can be risky for your device.