How do I get new uncirculated coins?

Excuse me, could you please clarify how one can acquire new, uncirculated coins? I'm interested in the process and wondering if there are specific steps or channels that I should be aware of to acquire such coins. Are they available directly from mints or is there a secondary market where I can find them? Additionally, are there any precautions I should take to ensure I'm purchasing authentic, uncirculated coins? I'd appreciate any insights you might have on this topic.