The Chainsaw Man manga came out in 2018 and the anime in 2022, so there's quite a time gap if you're waiting for new episodes. The manga has way more detail in the drawings and action sequences compared to the anime, especially in the fight scenes - you can follow what's happening better because you can look at the panels at your own pace. The anime on the other hand has the soundtrack and voice acting that give it a different vibe, but sometimes it skips scenes or cuts them down a lot for time reasons.
If you want to keep up with the story without waiting years, the manga is definitely the better choice. The first part wrapped up around 2020, the second one's still ongoing. With the anime you risk waiting a good while longer to see where the plot's going. That said, if you prefer video format and don't really care about staying caught up with everyone, watching the anime when it drops every now and then is fine - it's still well done and you still get the story.
Personally I read the manga when I want to unwind from lab work, it's faster and doesn't tie me to release schedules. It depends if you're the type who prefers reading or watching, but if you want the complete and fresh story the manga wins hands down.