Wait… what!? Neither.
And if it is, it isn’t “venture capital,” it’s predatory, please send whomever is trying to do this, this answer.
Venture Capital is capital invested in ventures. Invested means that it gets ownership. This is true of the word investment whether you’re buying stocks on Wall Street, buying shares in bulk in a Mutual Fund, acquiring ownership in a business, or getting equity in a startup.
Charging fees doesn’t even make sense. It’s a scam. Think about it; an organization is going to invest in you but you have to pay them to do so?!
Charging interest would make it a loan, I presume. If you have to pay back the money, plus interest, it’s financing, not an investment. Often investors will do such a thing through what’s known as a Convertible Note (which converts equity ownership instead of having to be paid back), but such a thing still isn’t called Venture Capital; though it may come from a venture capitalist (a partner in a Venture Capital Fund).