It's a very good investment to spent a week or a month (typically depending on age) to really learn hiragana. Learn hiragana and katakana in parallel. Use an app like 'Kana mind', for example, to enforce memorization.

Using romaji will, due to how the brain works, forever keep you out of learning kana properly, even when you see both at the same time. Learning kana is a small effort for a lot of gain.