Use Bitcoin. Bitcoin is digital cash you can hold and spend without permission.
With Bitcoin you can be your own bank, and a "self-custodial wallet" like Muun is the software that helps you do that.
Install the Muun Wallet app from the app store. Setup a secure pin then click "backup your wallet." Then click "I do not want to use my email." Then click "create an alternative backup" and follow the steps on screen.
Email is convenient but it's a privacy risk.
If someone is trying to send you Bitcoin, tap "receive" and choose "Lightning". This will generate a QR code invoice which can be scanned, or copied and sent via text. Think of it like a one-time use email address for receiving money.
If Lightning doesn't work, you can switch to the "Bitcoin" option to get a slower, less private "on-chain" address.
Most online services that accept Bitcoin work with QR codes. Tap "send" and scan that QR code with Muun to pay it.
If you're trying to send Bitcoin to someone else, ask them for a Lightning invoice or a Bitcoin address. And if you're both in the same place you can just scan the QR code on their screen.
Most stores and online retailers don't accept Bitcoin yet. The most popular way to spend Bitcoin (if you must!) on real goods in 2022 is to buy gift cards or single use credit cards. A few services to help you do this:
Gift cards and bill pay
Pay With Moon
Pay US merchants online
There's a lot to learn about Bitcoin, both what it is and how to use it best.