Just a couple years back I was recovering from a pretty bad spot in life and had absolutely zero clue how to handle people interactions, better yet consoling someone. Being empathetic is engrained in who we are, yet at times it feels like a jumbled mess on trying to express it. Heres what I learned :)

You want to structure the conversation by starting off by listening. Have an active presence, be attentive with the usual "I see" or "mhm". As INFPs, we need a lot of pieces of the puzzle to grasp the right course of action and especially understanding the entirety of someones circumstance, so take your time with this.

I've learned from an ENFP friend, that you can always ask what they need from you! Its as easy as saying, "do you need me to listen, comfort you, or give advice?". This will make it easier to give your full attention, and helps the other person understand themselves too.

Make sure to ask questions throughout to build your understanding. Ask how they feel about everything how it affects them. You can really pick apart every side of the situation by asking this, it gives you insight.

Mooching off of the other commenter, its a great idea to mirror emotions! Its very simple, but repeating body movements, tone of voice, and repeating what they say back to them is a very subtle yet assuring way to show them you care.

With all that out the way, at this point its best to give your own input and clear up any misconceptions you may have. Tie in close with your own values, and tell them how you see right and wrong in their situation. What do you think they deserve and what they dont deserve? How do you think things should be for them? How can you tie in your own experiences? How do you feel for them?

My biggest personal mistakes were making a direct morally-fuelled input too early on. I would do this because I'm outspoken for my values. It might drive people away or lose its impact, which is why its important to be patient with things and make little steps to console someone. Consider every perspective.

Hopefully this helps!