Migration from Mainframe Cobol using MF Enterprise Server

I'm afraid your question is not entirely clear.

Visual COBOL supports a number of COBOL dialects, including the "MF" dialect and various mainframe dialects. The dialect being used is independent of whether CICS APIs are invoked.

If you are migrating CICS applications that use BMS to communicate with TN3270 clients, and you wish to modernize those applications so they are no longer accessed through plain terminal sessions, there are various possibilities.

1. You can use a TN3270 "screen-scraping" product to translate between TN3270 datastreams and some other form of UI, typically a web page. Some products in the Micro Focus Connect portfolio provide this sort of feature.
2. You can write applications that use the EHLLAPI feature to automate TN3270 datastream processing, and deal with that data in whatever manner you wish. Again, see the Connect portfolio.
3. You can change your CICS applications to use some communications method other than BMS. This might include using the COMMAREA, or web-enabling the application using CICS Web Interface. This can be relatively straightforward, particularly if the business and presentation logic are separate. If you change the application to use the COMMAREA, you can then use the Interface Mapping Toolkit to create a service interface for it, or invoke the program using EXCI (External Call Interface).