Can I learn and do trading for month to make at least some money(around $100-$250), while doing freelance programming? I can arrange 3-5 hours for each activity per day.
Yes, you can. You are the one who knows how to manage your time better than us so I think you can work on both. Just don't set target profits as it might give you expectations.
Should I start trading on OTC exchange or regular exchange?
Trade on a trading platform
e.g Binance. That's where you can see a real trading action.
No need to undergo KYC here since you hate it. No shitty support here since you hate it. However, like in any reputable exchanges around, we can't take away the risks of placing funds here. But for now, we are minimizing the risk so stick with the reputable one.
I have spare $300 that my friend suggested to use to start cryptotrading, as this is the maximum amount of money affordable to lose. I have a month of free time to trade with btc. Currently I don't have income and I have three ways to set it: cryptotrading, freelancing as programmer, or full-time job. I chose to expirement and try luck with trading and freelancing, if there is no success with any for september, I will choose full-time job. If I can make about $500 per month with all of these methods or some of them, I can forget about job for a while, which is highly preferrable
Yes, you really need to undergo some test and not just a plan to see if it's effective in the long run.
However, earning in trading is not on a regular basis.
You can't just expect that wind will always head to the way you want. There are chances that you will have no income for the month of September but you will have a decent one in the following months. As I said above, don't set a given period where it's necessary to earn. It's not how trading should be. It might wreck your strategy if you keep on targeting fixed earnings on a monthly basis. Focus on maintaining winnings instead.