Hi Priya,
It depends on what your team feels is fun, things that have worked really well at Airmeet are having a meme channel to roast processes or even failure. helps add humour to everything that we do and minimises the friction between folks when they laugh at things together.
This is just one example, we do enjoy fun trivias, pet shows, travel diaries, sharing work from anywhere tips etc.
It is important as HR leaders that we should spend enough time understanding what ticks with the team and bring those flavors into the org.