If you have access to the back-end of the store that you’re migrating from, then you’d want to use a migration service like Cart2Cart or LitExtension (or else hire a Shopify Partner to handle it for you).
If you have a CSV file with all of the order details, then you could use the Matrixify app (https://apps.shopify.com/excel-export-import). Their $50 plan allows for uploads of up to 10,000 orders at once. You can remove the app after you’ve finished uploading the orders, so that you’re not charged again the following month.
Then you can grow your import file from there by looking into our Orders Documentation page where you can download full and simplified Orders Demo files as well as see each column from our template explained - https://matrixify.app/documentation/orders/
You can test the app and its process with free Demo plan that supports up to 10 Orders at a time.