Yep, get a controller, lol!
Seriously, there is an article (bit older) somewhere on the blog where Phil explains about his starting digital DJ-ing with only the keyboard shortcuts. Interesting read and although it’s proof positive that it is possible, you’ll see that he does think it’s way easier and more fun to use a controller.
Moneywise getting a controller shouldn’t be a problem anymore these days. 300 euro buys you a Reloop BeatMix 4 with a full version of Serato, just to name the current “pick of the month” (just because it’s a great starting controller and it comes with a full version of one of the most popular DJ software packages, which is rare – most come with a rather useless LE version that requires additional money to upgrade to the full version).
And the extra amount of pleasure you’ll have from using a controller is definitely worth it, imho.
Warning though: this stuff CAN be highly addictive (and usually is).
Welcome to the forums.
Greetinx.