You have to apply through icann to provide a new top level gtld. See their site at https://newgtlds.icann.org/ it has all of the information. I have heard/read somewhere that the initial investment is like $100,000
To become a registrar, you'll need to apply to ICANN to get registrar accreditation. There are some fees associated with that, plus ongoing compliance work that you'll need to do. If you're getting started out, reselling via another registrar is a much better option, most are willing to give you a free account to sign up, although you may need to make an initial deposit. Even big hosts like DreamHost were on another reseller for quite some time before they eventually achieved registrar accreditation.
To own a new TLD, you'll need to wait until the next time that they're looking for applications for new TLDs, and submit a proposal plus pay the fee - those fees are not cheap.
I am not sure if you can create your own TLD. That's ICANN's job- to release the TLDs. That too I guess is done as per market demands.
Becoming a registrar is a task. In the sense, you have to first get accreditation from ICANN to become one and in order to do so, there is a one-time application fee of $3500 (USD). Along with that, there is a whole list of documents you need to submit to tell ICANN that you are a stable business. To prove that, you as an organization need at least USD 70,000 of liquid working capital.
Once you are registered, you have to pay USD 4000 annually to ICANN as a membership fee. I understand, for some organizations, it can be a bit too much, which is why only certain organizations get to become a registrar.
During the process of submitting documents, ICANN has certain checks and balances in place. Like they look at certain projections for the fiscal year just to ensure that your financials are at par with the industry standards, you have proper documentation in place as per the RAA (Registrar Accreditation Agreement) etc.
All of this is tedious and also long in terms of procedure. You can check out the details on ICANN's website if need be. Some players in the market approach consultants to take care of this aspect, like LogicBoxes etc.
But yeah, this is how it happens because if you come to think of it, it is someone's online entity at stake, which is why ICANN needs to ensure everything is in place.
For that my friend, you would need professional help from consultants who can help you put up an application with ICANN to be applied as an Accredited Registrar.
Once your application is reviewed and approved, ICANN will further notify and put you in touch with various registry operators (.com, .net, .org, .co, .biz, etc..) for you to be able to discuss and work out specific terms to be able to sell their TLDs on your registrar platform.
Put up an application with ICANN to be applied as an Accredited Registrar. Once your application is reviewed and approved, ICANN will further notify and put you in touch with various registry operators (.com, .net, .org, .co, .biz, etc..) for you to be able to discuss and work out specific terms to be able to sell their TLDs on your registrar platform.