How do I add money from PayPal to Steam?

I'm curious to know how I can add funds from my PayPal account to my Steam wallet. As a frequent gamer and user of Steam's platform, I find it convenient to have my gaming purchases seamlessly integrated with my preferred payment method. Could you please provide a step-by-step guide on how to accomplish this? It would be especially helpful if you could outline any potential challenges or limitations I might encounter in the process, as well as any alternatives if PayPal isn't an option for me. Thank you for your assistance in this matter.