Here are suggestions:
Message, text or email them your love and concern. Short and sweet: “I’m so sorry for your loss. I’m so glad you are alive.” “I love you” is nice too.
Listen. Everyone’s experience of this tragedy is be different. It helps when someone simply listens to how it is for her or him. Don’t offer advice or stories about others’ loss: just listen.
Send a gift card or offer financial help: Your friends are going to be spending money for to meet so many needs. Grocery stores and restaurants cards are especially useful, since insurance claims take time to process, even in the best of times.
Make a meal or shop for groceries. Food is comforting and vital to help tired people. Your friends may not want company, but a meal may be welcome. Your contribution helps even if your friends are being staying with loved ones.
Ask to run errands or drive them. Deliver right to their door. If they want to do their own shopping, having you chauffeur can take some pressure off.
Ask children what they need. Is there a game or toy a child is missing because of the fire? Deliver that to the family. Helping the children helps the family.
Be there for the months ahead. Rebuilding after this disaster is going to take time. It’s important to be there for your friends now and in the future. All the kindnesses and caring actions above will help for a long time to come.