Bakery and restaurant

In My opinion no separate registration required,

1. In Bakery only a supply of goods i.e. food items but there is no element of supply of service. Hence @ 1% GST payable under the composition scheme, in the Traders category.
2. In Restaurant service  Supply of bakery products,  packaged food being namkeen, sweet, bakery product is being sold by the restaurant the same will be taxable @ 5% without ITC under composition scheme in the Restaurant  Services category  additionally remember that if bakery and restaurant at same premises than composite supply cover @ 5% in Restaurant service.

Yes. There is no restriction.

You can pay GST at 1% on sale of products and GST at 5% in restaurant services. Both under composition scheme of a single GST registration.