Development should be done using aspnet boiler plate and devexpress/devextreme
Business logic is basically upload CSV file. Create a background task to process the CSV file and generate an excel file based on that csv file.
Eventually integrate it with aspnetzero and make it subscription based application.
21 фрилансеров(-а) в среднем готовы выполнить эту работу за $699
i am a lead .NET software engineer and responsible for creating a web and desktop applications using different languages and technologies if u r interested just send me a message thank you and good luck