It depends on personal preference. Some people might think the manga is better for its original storytelling and art style. Others might prefer the anime for its animation and voice acting.
The connection between the anime and specific manga chapters isn't straightforward. It often depends on the creative decisions of the production team to adapt the story effectively.
I'd suggest starting from the beginning of the manga. Sometimes the anime leaves out little details or nuances that you can catch in the original source. Plus, it'll give you a deeper understanding of the story and characters.
Spy x Family manga has wrapped up. It provided a conclusive and fulfilling storyline that wrapped up all the loose ends. Now you can binge-read the entire series without any interruptions.