I bought Minecraft on my Android phone and now want to play it on PC do I have to buy it again?
Yes you have to.
Yeah, probably. So if you want to play Java Edition definitely.
(If you no longer want to play Minecraft on your phone, you can have it refunded, which means that you get your money back on your credit card or whatever.)
Yes. These are two completely different versions.
Yes you have to.
What do you actually wish for?
Do you want to save money with it?
The Minecraft PE version costs around -. 5 euro, the Pc version costs around -. 20 euro. Logically you get more updates for the PC version, for example, and you have more options in the game.
That does not work
Yes, it works. In any case with an Android device.
No.
You can get a refund for any app in the Google Playstore that cost money. The app is automatically deleted from your mobile phone and you get the money either on your Google Play credit or on your credit card, etc.
but this has nothing to do with the PC version of Minecraft!