SAP FICA is a subledger accounting component designed for industries with a very large number of customers and a very high volume of small, repetitive transactions. Where standard SAP FI Accounts Receivable is built around customer accounts and invoices, FICA is built around contract accounts and business partners, and it handles the full life cycle from posting a bill to clearing the payment.
https://www.proexcellency.com/blogs/sap-online-training/best-sap-fica-online-training-with-real-time-projects-and-certification-support