You’re not already good skiers than snowboarding has a faster learning curve. Although, if this is a passion you think you’ll have for a long time than skiing is probably easier for older people provided you mastered the sport while young. I still see 60-70 year olds skiing but most snowboarders are younger than 60.
If you’ve never skied or snowboarded before take a lesson. I’d almost guarantee you’d be having fun on a snowboard faster. It’ll take a few falls for your muscle memory to kick in on a snowboard but by the third days you’ll be having a blast. A nice thing about snowboarding is if you end up on a slope over your ability, it will be much easier to get down that slope boarding. If that was to happen on ski’s you’d be forced to take them off & walk. It would behove you to squeeze in at least one lesson between now & your trip if you have the chance.
Wear helmets!