Ya'll recommend first learning word in hiragana/katakana or learning kanjis to start learning how to organize your thoughts when writing in japanese?..
Just learn how to say the words first (i.e. the kana form). You'll acquire kanji gradually as you go, so it's fine if you can't read/write the kanji form right off the bat. It takes time to build up.
I would say to start doing kanji alongside hirigana and katakana. A friend of mine recommended doing so and it has helped, afterall there is over 6,000 kanjis.
The standard progression supported by renshuu is to learn all the kana first, then begin with vocabulary, and gradually introduce kanji after a few hundred words. This is the best order for most people, but if it isn’t working for you, it’s also possible to shake it up a little by delaying the kana and/or accelerating the kanji. However, if you do this, you will not get support from renshuu. It just isn’t set up that way.
Some people don't even learn kanji separately from vocabulary, personally I don't think there's anything with having vocabulary with kanji/furigana basically immediately. Then just do the kanji schedules whenever you feel like it.