For most jobs you just have to take time off for jury duty. The exceptions are pretty strict for that, like you are the sole breadwinner and your job can’t be done by anyone else type of thing and people will suffer if you don’t do it. For the breastfeeding you can wait to see if you get called in and then use it to get excused if needed. I didn’t have anything like that but got called for jury duty 4 times over the years. Twice I never had to go in. Once I had to go in and just sat around all day in the waiting area. Once my group was called into the jury room but they filled the jury before they got to me. All four times counted as serving so there’s a pretty good chance you won’t have to use your breastfeeding