There are actually 3 things which are been excluded from GST (goods and service tax).
Petroleum products
There are a variant of products which comes under the petroleum products such as Petroleum crude, motor spirit (petrol), high-speed diesel, natural gas, and aviation turbine fuel etc. which are excluded and no taxes are imposed on these products.
Alcohol
Alcohol consumed by humans have not been included in the purview of GST in India at the current time. So it is been sell at the prices as it was before the implementation of GST in India.
Electricity
Electricity is the last thing which was put aside under purview of GST. So articles also don’t fall under the category under which GST is imposed.