If any aspiring Japanese learners read this, forget this article. Just start learning hiragana/katakana from the get-go. You’re going to have to eventually, assuming you want read anything (and anything worth reading certainly won’t be written in romaji). But beyond that, you want to start breaking down your instinctual pronunciations and biases that appear when reading letters you know, so that you can more accurately and efficiently learn the correct pronunciations.
This is unnecessarily pedantic advice, and I encourage fellow learners of Japanese to ignore it. You will definitely need to learn hiragana and katakana but you can do it at your own pace, and it is orthogonal to learning the basics of grammar, forming sentences, and pronunciation, so you definitely don't need to think of it as an obstacle. For pronunciation in particular, obviously watching Japanese movies etc helps. And yes, I have a native Japanese teacher who recommends the same.