You’re a single mummy. I don’t think you need to give ang pows to anyone unless you want to and have the means to.
As for visiting your in laws and visiting that side of the relatives, it depends on your relationship with them. If they’ve always been nice to you but this relationship got messed up because of your ex-husband, then would be good to at least bring mandarin oranges when you visit them. I personally would only visit them and not the relatives, but that’s up to you I guess. If I did visit relatives, I would also give oranges to elders as a form of respect. If your in laws and you have never been close, then politely decline?
At this point, you need to live for yourself and your child. So do what would make both of you happy. Proud of you for being so strong. Hugs ❤️