Climbing stairs is probably one of the best exercises you can do when preparing for hiking. You can do them outdoors or indoors (in a tall building if available). Even better, add a backpack with some extra weight when doing stairs and if possible wear the same hiking shoes as if you were hiking. You can also do some uphill runs, uphill jumping squats and lunges going uphill as well. Another option would be to go for some runs on the sand or grass to increase the strength and stamina in your legs. Again, if you can perform these exercises with a backpack it will be great.
When walking around and running errands, try to carry a backpack with you so you can create similar conditions to your hiking. There are many more ways to train for a hiking trip, but in my opinion I believe these are few good options for you to follow.
I hope this helps!