Registration

Yes, You can. Once a taxable person is registered under GST Act, he is bound to pay GST, even if his turn over is below the prescribed limit.

Yes you can apply for GST Registration on Voluntary basis. The GST Law vide Section 25(3) of the CGST Act 2017, allows person to register under GST on "Voluntary basis" i.e. registration is possible even if your Aggregate Turnover is less than Rs. 10 lakhs or Rs. 20 lakhs or Rs. 40 lakhs, as the case may be.

Small businesses with turnover less than 20lakhs can voluntarily register under GST.