You can use the POST https://<URL_of_the_Instance>/api/data/v1/Account API to create an account. Use the following sample payload to create an account:

Only the Name and Price List are required.

{
  "Name": "Conga Account",
  "PriceList": {
    "Id": "Guid",
    "Name": "PriceList Name"
   },
  "BillingAddress": "Billing Address",
  "BillingCity": "Billing City",
  "BillingCountry": "Billing Country",
  "BillingCountryCode": "Billing Country Code",
  "BillingPostalCode": "Billing Postal Code",
  "BillingState": "Billing State",
  "BillingStreet": "Billing Street",
  "ShippingAddress": "Shipping Address",
  "ShippingCity": "Shipping City",
  "ShippingCountry": "Shipping Country",
  "ShippingCountryCode": "Shipping Country Code",
  "ShippingPostalCode": "Shipping Postal Code",
  "ShippingState": "Shipping State",
  "ShippingStreet": "Shipping Street"
 }
CODE

Next Step: Create a Price List.