Hey, @ppeshopsonline! Great question. Which payment gateway are you using?
If you are using a third party gateway, please contact your payment provider directly to inquire about the currencies and ways they handle payments and payouts.
However, if your store is based in the USA and you are using Shopify Payments, then yes you can have your customers pay in USD. Check out the Location and Currency FAQ for Shopify Payments which has answers to more questions like these.
That being said, also when using Shopify Payments, it’s possible for the currency that your customers use to pay for their orders be different from the currency of your payouts (ie. your store currency can be different from the currency of your bank account). So, if you did want to allow your customers to pay in Mexican Pesos (or offer multiple currencies to your customers), then they could do that, and you would still be able to receive your payouts in US Dollars. Does that make sense?
Let me know if you have any other questions, or need further clarification about this. I’m happy to help!