How do you redeem a fund?

Could you please elaborate on the process of redeeming a fund? I'm particularly interested in understanding the steps involved, any prerequisites or conditions that need to be met, and if there are any fees associated with the redemption process. Additionally, I'd like to know if the redemption process differs for various types of funds, such as mutual funds, exchange-traded funds (ETFs), or cryptocurrency funds. Lastly, is there a specific timeframe in which the redeemed funds are credited back to the investor's account?