These are many questions at once, which can not be answered on a general basis.

The current LOGO! 0BA8 can manage the following hardware:
Digital inputs: 24
Digital outputs: 20
Analog inputs: 8
Analog Outputs: 8

A LOGO! 0BA8 base modul has 8 digital inputs and 4 digital outputs.
Depending on the selection, there is the base module with 4 analog inputs (0-10V) and 4 fast counter inputs. This means, for example, if you use 2 analog inputs and 2 fast counter inputs, then there are only 4 normal inputs. The base module has only one Ethernet port.
Digital expansion modules are available in 2 basic versions:
- DM8, 4 digital inputs and 4 digital outputs.
- DM16, 8 digital inputs and 8 digital outputs.
Digital expansion modules do not have analog inputs or fast counter inputs.
Analog input modules have two analog inputs, it can be selected between 0-10V or 0 / 4-20mA.
Analog output modules have 2 analog outputs, it can be selected between 0-10V or 0 / 4-20mA.
Then there is an analog expansion module for temperature measurement with PT100.

Edit:

The software for programming the LOGO! You must purchase as a single license.
You must also purchase the software for programming the HMI as a single license.
If you buy the corresponding Starter Kit from LOGO, the software for the LOGO! And for the HMI therein.

You can use both panels. Depending on whether you choose a Basic or Comfort Panel, you need different software.

For a Basic Panel, WinCC Basic is sufficient. If you take a Comfort Panel, you need WinCC Comfort (of course more expensive).

Siemens has a website with application examples.

Application examples for LOGO!

There are also examples of communication between LOGO! And WinCC.