How do these two websites relate to one another?

[Tetsuya]

Hi, would you please tell me how the following two websites relate to one another?

1. https://www.migaku.io
2. https://www.patreon.com

• Do I have two different accounts on each website?
• If so, which account should I use to log into the extension to make flash cards?
• Does my subscription on one website transfer to the other?

Thanks in advance!