what are the procedure to start a proprietorship consultancy company?

It is possible to start you business with nothing. You don't even need to register a business name.

Basically you trade under your own name. Any income to the business is part of your personal income.

You can register a business name, to look more professional. You can even register a logo, but that is more expensive and basically a waste of time (only the big companies register their logo).

If you want to set up a company the process is fairly straight forward and there are a number of tax advantages that will differ between states (and obviously countries).

I recommend that you go visit an accountant (the accountants fee is a tax deductable expense) to get the best advice.

Setting up a company (limited liability) has the advantage that if something goes wrong and someone sues the company you are limited in your personal responsibility, while if you operate a proprietorship you are the company and they would sue you directly.