Just go out and do stuff you enjoy and the money will follow. I’m a corporate drone, but before kids, I had spare time to do stuff and money just fell onto my lap in unexpected ways. They key is to be prepared so you are able to take the opportunities that come your way.
I was interested in certain technical gizmos, so I found one online in eBay and used it and it was good and bought a job lot of 100 from the seller and re-sold it at higher prices after packaging it into a kit. Then I did a deal with the seller, figuring out his source and got exclusive on the source and also bought more peripherals to sell with it. It was a mini-business, but I did it for the fun/challenge. I don’t recommend physical businesses as you have to deal with inventory and it is hard to scale, but it is good for learning (plus all the scammers that come after you etc. etc.)
Later, I got interested in computers and made a few websites. When the law in the UK changed requiring people to get an energy performance certificate, I grabbed a relevant domain, threw a bit of content on there and put google ads on there which generated monthly income without any work. Similarly, I had a hobby website and put adverts on there and found certain few pages got lots of hits and made decent money.
Another was that I got an android phone for the first time and then wanted to learn to program for it and learned java and wrote some apps that I wanted. I released them all for free and got many downloads. Then just on a whim, I released exactly the same app, but as a $1 paid app and the amazing thing was that people would pay for the app even though there was an identical free app available! I wrote more and more apps and in the space of 4 months was pulling in 3-4 figures a month in sales which was very lucrative as after Google’s cut it was pure profit with zero cost of goods (compared to ebay business where you had to buy stock, pay for postage and packaging, buffer for returns, thefts etc.).
I had to decide whether to pursue that full time or take another opportunity and took the other opportunity which didn’t give me free time to do this any more. Before I had a 9-5 job and it was very easy so I had energy to spend another 5 hours working on apps in the evening. The new job was financially rewarding but burned me out.
I think you have to just get out there and try stuff. There’s a stat about how many businesses fail and it is a big portion, so you just have to try, see some fail, learn from it and try again until you get it right.
But instead trying to start a business, why not work on your hobbies that you like and then see if the things you do can be monetized? e.g. do whatever you’re doing and record it and put it on youtube. If you make something, put it out there for free with donations, or sell it.