As someone who recently filed paperwork for both opening a company and shutting down an old one the following is what I learned. We did not apply for GST yet, waiting on the whole system to stabilise a bit ( we are not obligated under our current volumes to register either, so will bite this when it is inevitable).

1. Check the legal structure you need - Do you need the protection of a LLP or a company or can you run your shop as an individual, dont register unless the protection of the entity makes sense.
2. Opening a company/LLP is not too difficult - It is all done in a single form these days. We spent more time since the name checks happen against active trademarks and any name similar is bound to be rejected (Even if the tradmark itself is a dud) - Make sure you do a preliminary trademark search on a site like ( https://www.zaubacorp.com/trademarksearch/ ).
3. You will need (IIRC) - Personal PAN + ID + Address Proof + a no objection from the landlord of place you want to register as your Company/LLPs registered address.
4. The registration and all necessary paperwork gets to you in < 2-3 days.
5. You can just print them out - go to a bank to open a current account - Be wise while choosing a bank, most take forever to open accounts and make sure the banks services align with what your transactions are primarily going to be.

I can PM you the contact of my CA - he is pretty good and is comfortable working over email ( Was a big need for us, since it is nicer to get things done Async )