Can someone make it trading only altcoins?
Of course you can, I also trade on altcoin, I don't have Bitcoin, because the current price of bitcoin is still expensive, and in altcoin everything is still cheap, so I decided to altcoin, and I'm grateful to be profitable
The reward is pretty less as compared to the risk that you are taking and if you don't have a clue about trading and are doing a fresh start with trading then I wouldn't advice you to do so, I have seen a lot of people getting REKT while trading in just a single bad trade and it took them months to build that amount of funds that were lost in a single trade due to the unpredictable market. First you should learn trading cryptocurrencies and then practice the strategies told in a practice account and when you feel confident enough to conquer the market, you should finally start with a small amount of capital and try to make it big instead of starting with loads of money initially.