Primarily, it's important you know your market and know who exactly it is you're trying to appeal to. Are you fixed on the idea of a store or are you also interested in eCommerce? Fashion is an extremely restrictive business, mainly due to the competition that's out there! Before asking anyone for money, you need to have a clear focus on what your plan is and this needs to be conveyed to them. Nobody will hand cash over to you unless they're sure they believe it will yield a return (unless they're taking an extreme risk, but.. In times like these that's obviously highly unlikely).
There's no rules on what experience you have to have, so no, business management courses are not essential. The benefits are clear, however, if you should decide to take a business management course. Start out by doing some market research in your speciality then go from there!
Good luck,
Sean
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