Converting cash to crypto is tricky but doable. You're getting into grey and black market territory, meaning you're open to getting scammed or hacked, so just be careful.
Goodluck not getting picked up by the Feds for using this:
https://localbitcoins.com/
If you wanna fly under the radar get some Bitcoin on a site like Coinbase, then convert it to Monero on Changelly or some other Atomic Swap site. Actually try to avoid Changelly for Monero if you can since they may ask for KYC. I believe the Coinomi wallet also you to hot swap Monero too without KYC.
Once your funds are in Monero you can do whatever without anyone ever knowing, just please use a VPN while doing this to be extra sure. You will seriously want some Black/Grey market funds for when the NWO has full power for fake IDs, vaccination cards, guns/ammo, and whatever "illegal".