dragnil

Hi, Nikon user since 1965 and trying the X T5 with 150-600mm for wildlife and birds. So far it seems very good but I'm still struggling with the huge number of options in the menus. So, here's my question, when and why should I use either 117 or 425 focus points. I'm usually on zone focussing with"bird recognition" selected (how do they do this?). What are the pros and cons please of the two options. Thanks in advance. David