2600ft is not high. There's no significant effect on oxygen levels, ability to breathe, boil water, lighting a fire or anything like that. It's practically the same as at sea level.
Now this is embarrassing but regarding lighting a fire, I will say that I have never managed to light a fire in the forest in winter with matches. Fortunately it was always more of a nice to have on camping trips not a need. But every time I tried 4 or 5 times, I failed. Matches would light as normal, but wood would just not catch fire. Freshly chopped or found dead wood... neither works because fresh wood is moist and dead wood in the winter is the same because it got rained on, snowed on, there's ice in the pores of the wood and when you hold a match to it, it melts and makes the wood wet. Summer is different because dry dead wood is abundant.
I've only ever had success using some kind of fire starter liquid, the most low-tech is wax from a candle which kind of works. And of course special products made for this purpose which we had with us most of the time make the task super easy.