What if altcoin/btc crash? Are there possible ways to get our money back?
Nope. You'll get nothing back if both bitcoin and alt coin market crash. Don't expect returns because nothing will ever return to your hands once all of the cryptocurrency market start crumlbing down. I think this should be a rookie thing to know since you're investing.
There is nothing we can do if altcoin and bitcoin crash and we cannot make anything. But we still have the coin in our wallet (if you use personal wallet), but if you use the exchange wallet, then you might lose everything. Although you save in your wallet, you cannot get your money back because it's not worthless and it only stays in your wallet without you can sell. The market will crash, every people wants to get their money back, I cannot imagine what will happen at that moment.