Can someone make it trading only altcoins?
That's very much possible but you will have to be experienced and has a high capital for you to be able to start. Like you as a newbie, you need to gain experience first. It's not just you have heard that they can make money through trading altcoins and so you'll do as well.
It takes time to tango and you have to practice yourself doing it again and again until you become familiarize with the setting in trading. Many day traders are prone to losing than profiting.
One does not necessarily need high capital to start. I know people who started from 100$ and now trade cryptos worth more than a hundred thousand dollars. It’s all about making the right decisions at the right time and understanding the market inside out. I agree that many traders lose money instead of making profit out of the trade the reason being their impulsiveness to invest without any background check or technical analysis.