How much does government spending impact inflation?

More specifically, when compared to consumer demand, who's contributing to it more?

I'm genuinely curious because of something JP said today — it's that he doesn't play a role in managing federal spending which lead me to wonder how the government's spending is impacting inflation over what consumer demand actually is. If it's much more than consumer demand, why on earth should consumers demand less when a behemoth like the federal government has unchecked spending? Moreover, spending that is money we'll all have to pay off and funny enough, something JP can't manage yet is tasked with worrying about consumer demand instead.

When the government demands money, do they even have to pay the fed funds rate? Or is this something specifically designed for consumers?