Well, it depends on various things like niche of the brand and the way it takes to grow on digital platforms(organically or non-organically). If the brand's niche is something like which doesn't have a large potential customers or not in trending, it takes more time and on opposite of that, it takes less time. Similarly if brand using organic method, it would take more time than the one which taking non-organic method like paid marketing.

Well, It depends on the basis of reason and the purpose of the website to create but minimum time any website would take to build is 18-20 days.

Both ways are good in the time of specific needs, for like if you want to build your audience who regularly engage with you, organic way is more sensible, and if you want to convert your potential customers into real customers, best way is non-organic way.