"To have a heart-to-heart with someone" means to have a deep and honest conversation with them about personal feepngs or issues. Here's an example sentence using this phrase: "I had a heart-to-heart with my friend about our relationship and it really helped us to understand each other better."

Another way to say this is "to have a candid conversation with someone." For example: "I needed to have a candid conversation with my boss about my concerns with the project, so I scheduled a meeting to talk it through."

Both of these phrases indicate that you are having a serious and open discussion with someone, where you share your thoughts and feepngs honestly and openly.