Let’s de-mystify the works of a ham radio connected to a computer. First, Digital Mode Operation is usually done with your computer sound card or an external device that has a sound card and interface in it, connected to the audio inputs and outputs as well as your PTT circuit in your rig.
Devices such as the Signalink USB, Rigblaster, Rascal, and others allow you to make these connections. A TNC, or Terminal Node Controller can also be used for some digital modes.
The other type of computer-to-rig connection is called “CAT” or “Computer Aided Transceiver” control. This involves using the serial port (also called COMport) of your computer to send binary codes to your rig to make it change frequencies, modes, filters, etc. without touching the rig itself. All rigs differ but have some type of CAT connection, and a serial cable with some type of converter built-in is used for the connection to the computer. This may even involve a USB connection, with a software driver known as a “virtual serial port”.
If you plan to be able to control your rig and do digital mode communications at the same time, you will need both types of connections. There probably are some devices out there that can do both.
Then there is software. The internet is full of free software that will do both functions. And there are also versions you buy. And some rig manufacturers offer their own versions of control software. BUT…. setup is not for the faint of heart! You will need good knowledge of how to hook up and run your computer, and your rig, and how to add and set up the software that you will need.
I personally recommend that beginners wanting to do digital mode operations go slow, go simple, and not try to do too many things at once. A good digital Elmer would be a must. If you want to experiment with CAT control, then play around with just it until you have “mastered” it. It can be a lot of fun, or it can be loads of frustration that will turn you off immediately. However, just remember, you will only get out of it what you put into it. Amateur radio is about learning. Don’t expect to be an expert right when you start.