No more than a subsistence living as a hunter-gatherer, and in fact, likely less so. If you live absolutely primitively, then your circumstances force you to align your life and habits to those behaviors that sustain life. There is something external to yourself which constrains the actions that contribute to your continued survival.
The whole idea of capitalism is this: If you want something you do not have, then you must offer to those who have it something that those people value. There is something external to yourself which constrains the actions that contribute to your continued survival. This may force you to align your life and habits differently than in the subsistence scenario, but not necessarily more so.
In each scenario, there are things you can control, namely your actions and behavior. You can take actions which convert into shelter, water, and food. Whether there is nature or human volition on the other side doesn't matter so much. There are actions you can take which support your survival, and actions which don't. That the actions are different is not germane to the question as posed - there are external constraints that determine which of your own actions contribute to life.
As a side note, there is nothing inherently uncapitalistic about the subsistence scenario[0]. If you build yourself a shelter, do you consider that you own the shelter and get to control its use? If you do, this is capitalistic.
[0] This is phrased as a negative on purpose. I am not claiming that the subsistence scenario is inherently capitalistic.