do I have to have an internet connection for it to work?
No. However you told us "I want to create a simple BLE that will "post" my website".
Bluetooth LE devices don't magically connect to the internet. It's like complaining that your Laptop can't view websites when you have no WiFi router.
if not - why do I need to use pi?
If you want the MDBT42Q to connect to the internet then you need something to act as a 'bridge' between bluetooth and the internet - like you need a WiFi router to connect your Laptop to the internet. That's what we're suggesting the Pi is for, but it's by no means the only thing you could use.
For instance using Web Bluetooth on a phone/tablet/laptop is super quick and easy:
Espruino is a JavaScript interpreter for low-power Microcontrollers. This site is both a support community for Espruino and a place to share what you are working on.
No.
Yes, it can work on its own just fine.
No. However you told us "I want to create a simple BLE that will "post" my website".
Bluetooth LE devices don't magically connect to the internet. It's like complaining that your Laptop can't view websites when you have no WiFi router.
If you want the MDBT42Q to connect to the internet then you need something to act as a 'bridge' between bluetooth and the internet - like you need a WiFi router to connect your Laptop to the internet. That's what we're suggesting the Pi is for, but it's by no means the only thing you could use.
For instance using Web Bluetooth on a phone/tablet/laptop is super quick and easy:
https://www.espruino.com/Web%20Bluetooth will show you how to create a website which will communicate with the MDBT42Q - but only when that webpage is open.
Still, that may be what you want?
This is just a super simple webpage which will output whatever text your MDBT42Q decides to print. You can then do with that what you want.