Hey, well, your word choice is interesting because it depends on if you mean healthy by God’s standards or by the world’s standards. By the world’s standards, it’s okay to flirt in guy/girl friendship which some people think is harmless but the truth is lines are never really defined, it’s never clear to either party how far is too far and honestly, it leads to a lot of unfulfilled expectation and a lot of confusion so I’m gonna talk to you about godly friendship between a guy and girl. The Bible doesn’t really have specific verses on the topic but it’s pretty clear what friendship looks like in God’s plan:
Let no corrupting talk come out of your mouths, but only such as is good for building up, as fits the occasion, that it may give grace to those who hear. And do not grieve the Holy Spirit of God, by whom you were sealed for the day of redemption. Let all bitterness and wrath and anger and clamor and slander be put away from you, along with all malice. Be kind to one another, tenderhearted, forgiving one another, as God in Christ forgave you – Ephesians 4:29-32
The key part of that is the “building up” part, a healthy friendship by God’s standards will not break you down, it will not shoot down your dreams, rather, you will flourish, you will become, more and more, who God wants you to be, there will be acceptance, love, sincerity and kindness and not the forced kind either.
And it’s really important that a friendship between a boy and a girl does not hinder purity – and purity is not merely wearing a ring and promising yourself that you will abstain from sex. It’s deciding to follow after God wholeheartedly, to belong to Him in every way and those decisions – sexual abstinence, refraining from using crude language, not watching or listening to anything that’s likely to lead you astray – they all come from that sincere decision to keep Jesus at the centre of your life.
hope i helped?