Would this work on my Note 9 if i did the following, i've got the car charger below, it was one i bought for my Note 5, it's an official Samsung car charger
https://www.mobilefun.co.uk/official-samsung-adaptive-fast-car-charger-black-53946
Would i be able to just change the cable on that to a USB-C cable or do i need to change the whole thing and buy the equivalent for a Note 9 ?
Yes that will work