For the first sentence, canopy is great. A tarp also covers things (for example, a bale of hay), but not usually so far off the ground. And Mikkel is correct; it's rucksack. If it's carried on the back, you can also say backpack. For the second sentence, I usually hear "bus stop shelter." Canopy would be understood, but it's not common usage. Hope this helps. :-)

Notice, it's "rucksack" not "racksack". The best I, as a non-native speaker, can come up with is 1. We put our rucksacks and firewood under a (improvised) tarpaulin shelter. 2. Several people are waiting out the rain under a bus stop shelter.