Mutual Fund, Index Fund, ETF, BTC ETF?

Before i start, hope i get this right

1)Mutual Fund = A fund where gather lots of money from multiple parties, and invest in either stocks or bond or even both, whole fund trading is perform by fund manager.

2)Index Fund = Fund that is invest in the entire index like the top500 stocks in US, or something, operates by fund manager too.

3)ETF = Similar like a Mutual Fund, but instead of investing to companies, it is traded on exchanges, works like how mutual works.

Am i right regarding on all this?

Then,

BTC ETF = A fund that is available on a specific exchange, the allocate fund will be invested into btc and the profit will come from the trading of bitcoin itself and distribute to the ETF holder within a specific timeframe.

Am i right on this?

Therefore Bitcoin ETF from winklevoss will be only trading on Bitcoin but not other coins right?

Thanks!