Q.Hibiscus
Does the hibiscus need lots of sun or moderate shade? Is it possible to plant in the ground or do we have to keep it in the pot?

Six hours of sunlight is a good amount.
If your plant receives less sunlight, it will still grow but may have less flowers!
If you are in a cold climate you should keep your Hibiscus in a container, so that you can move it indoors to winter over.
Here are some articles with more information.
https://www.gardeningknowhow.com/ornamental/flowers/hibiscus/how-to-care-for-hibiscus-plants.htm
https://www.gardeningknowhow.com/ornamental/flowers/hibiscus/wintering-hibiscus-indoors-winter-care-for-hibiscus.htm