
A lack of self confidence isn’t a turnoff, but confidence is a turn on. That said, once your in a relationship, the dynamics of how to be present and invested in the relationship usually involve taking initiative, so if you’re gonna have issues with that, then you’re gonna have huge problems in your relationship.
I agree with this, that said, it’s more attractive if you carry yourself confidently. It’s not a turn off (to me at least) if you open up about insecurities or worries you have. If you’re insecure about your looks with a partner, just try and trust that they like you for you despite any flaws you think you have in yourself