Help with Vit C and HA

Can someone help me understand the difference? I’m wanting to introduce Vitamin C and HA into my skin care regimen. Headed to Walmart and I see:

  1. Moisturizer with Pro Retinol, Vitamin C, and HA
  2. Pure Vitamin C serum + HA Serum

Wouldn’t the moisturizer be the best option? I’m headed to Wal Mart in an hour!