I think the best advice I can give is to reach out to people and have normal conversations when you don't need anything. If you only talk to people when you need something from them, they are going to be less likely to talk about things that they have going on outside of work. Talk about anything that they are interested in. Plus the beauty of messaging apps is that people can respond when they have time and if they are busy they can ignore the messages.
Also if you get some downtime in meetings or join early, ask how things are going, what the weather is like, or if they have any weekend plans. There usually is a bit of time before or after meetings where you can still socialize.