You don't need anywhere close to $10,000 to get into an S&P 500 or total market index fund (the latter probably better, if only for extra diversification). Just look for something cheap (expenses are commonly as low as 0.05% to 0.03%), including any account fees, and doesn't require paying brokerage commissions to buy or sell shares).

What's an S&P 500 "premium" index fund? Is it just super-cheap because of a $10,000 minimum? That's good.

On the other hand the index fund is "premium" because it tries to outperform the S&P 500, avoid it because there have been many attempts at "enhanced" indexing, and I don't think any of them beat their benchmark indexes in the long term and actually probably did worse than regular index funds because of the higher expenses. An example of enhancement not working happened when Wells Fargo was trying to invent the index fund for the Samsonite Luggage Co. pension fund in the late 1960s or early 1970s. They tried to weed out "inferior" stocks from their index, but those stocks outperformed the "better" stocks.