Depends how many trips you’re doing and how far you’re going vs how long you’re staying.
The 14 day pass for our three bullet train rides and random jr train rides wasn’t worth it for us, so we just loaded an IC card(Suica app) with some yen and bought our bullet train tickets individually on Klook.
The JR pass doesn’t work on all the trains but the IC card works on trains and busses minus the bullet trains.