Although, it is NOT advisable to transact with crypto in a country where it is "illegal", the very nature of Blockchain (permissionless) allows anyone to access it at will. Laws/regulations can't be enforced on a decentralized network. Only on centralized exchanges and/or centralized wallet providers. What's stopping people from using crypto "under the radar"? Of course, expect to face fines or jail time if you're caught doing this. You'd need to decide whenever it's worth taking the risk or not.
OP should forget about big purchases like houses and expensive cars because his money comes from an illegal asset in his country. But no one can stop him from paying individuals in bitcoin and receiving goods and services in return. Also, no one can stop him from exchanging his bitcoin to fiat and using the cash however he sees fit.
There are several risk factors attached to using gambling for transactions in a country where it is declared illegal. Because of the nature of Bitcoin, as a decentralized system, it has made it extremely difficult for the central government or any type of government to have control over the digital financial system. So, the government may not necessarily be able to completely stop the use of the bitcoin or cryptocurrency but you are more exposed to lost of your digital assets through seizures especially if such transactions are traced to any suspicion.
For instance, if your real estate transactions run in billions of dollars and the transactions were trailed to your account, government might find its way to seize such funds and the worse of it is that you cannot reclaim the lost financial assets through any legal process since it's already flagged as an illegal currency.