Download a statement from your bank as a CSV or Excel file (keep it under 5 MB), then head to Transactions and choose Import transactions. To import into one specific account, open that account's card menu and choose Import into this account instead — it will already be selected as the destination.
If your file doesn't have a header row with column names, don't worry — just flip on File doesn't have header and you'll be able to name each column yourself. Dates written like 7/31/26 are fine: Rasa Money recognises short years and unpadded months and days.