Yes, learn Hiragana and Katakana first. It doesn't take that long. Young people can do it in days or a week, I took about a month or so. But, unlike what I did, and many others do, I recommend learning Hiragana and Katakana at the same time. Most people learn Hiragana first and Katakana second, and will run into trouble with the latter, which also sometimes confuses the Hiragana they have already learned. Imagine learning the alphabet: Do you think it's better to first learn "ABCDEFGH.." and so on and then, after mastering that, start learning "abcdefgh.." Or wouldn't it be better to learn "Aa Bb Cc Dd Ee Ff Gg Hh.. " right from the start. I'm now a firm believer that the last method is better, and as you can think of Katakana as the cursive version of Hiragana (which is why it's used for loan words and also in literature for naming e.g. plant species, "Belladonna"), it makes sense to learn them at the same time. Faster, and avoids later confusion.