AWS has a free tier that lasts for a year. I actually used it to get hands-on experience with enough services that I was able to get my AWS Certified Solutions Architect, Cloud Practitioner and Certified Developer certifications. I easily spent 60 hours creating and deleting services and it didn't cost me a cent.

I don't even know how you'd accidentally get to thousands of dollars accidentally unless you were doing something more complicated like setting up an autoscaling group.

Spin up a t3a.micro EC2 instance and run it as much as you like - it's free. If you go into it (as I did many years ago) thinking, "Let me just spin up a 16 core server with 128 GB of RAM" because that's what you'd set up in your on-prem data center then of course you're going to have a big bill.

But that's not what cloud is about. It's about resources popping in and out of existence for the minimal time and resources needed to accomplish a task.