If you want those "clean and straight" firework streaks, use an aperture of at least F8 with a tripod. Or can try to capture the fireworks handheld without any tripod, might get some interesting and nice shots
settings for cam to shoot fireworks.
set ISO to lowest (around ISO100)
Shutter 2-5secs (more or bulb mode using black card)
WhiteBalance set to florence
Use remote to trigger the shutter(if possible)
that's all for the "basic" setting
can experiment around with the Aperture/shutter.
Try using a ND4 filter(can help to "clear" some of the unwanted smoke created by the first few rnds of fireworks)