The crypto king, Bitcoin, is seen mainly as a store of value, like gold if you wish.
But now, there are sites out there like Blockfi, Celsius, Youhodler, where you can place your Bitcoin, and other cryptos, to earn interest, anything from around 6% to 12%, and if you keep up-to-date with it there are specials where you can earn 18% passively. You need to google it and see what else is out there. When you deposit crypto at such sites with the view of increasing your total crypto value, yes that increase will happen, but if the crypto loses value so will the value of interest you are earning. There is a risk involved, but there is risk involved with any form of investing.
There are not many places in Australia that will accept crypto as payment for goods, this is a slowly developing space. I like the thought of investing crypto for interest, then when you want to, you can convert that interest to AUD and send it to your bank account.
Here is a site that mentions use cases for crypto, not much in Australia, but if you purchase from overseas sites you may see something that would interest you -
https://99bitcoins.com/bitcoin/who-accepts/. Here is another -
https://usethebitcoin.com/list-of-online-stores-accepting-bitcoin/. Another is
https://cryptonews.com.au/guides/who-accepts-bitcoin-as-payment-in-australia. Another is
https://www.cryptomarkets.com.au/list-of-retailers-who-accept-bitcoin-in-australia/.
As for Romania, you will have to do a lot of googling.
I do not know if there are any everyday use cases yet, for Cardano (ADA). The intention is that will happen, but I know not when!
Research, research, and keep looking.