Minecraft Windows 10 - 1 game license 2 kids in same house want to play at same time - how?

I am getting conflicting answers to my question.

We just purchased Minecraft Windows 10 (April 2020) for my son. However, my daughter wants to play too at the same time and go into a realm to play with her brother. Playing on 2 separate computers in the same household. How can we do this without having to purchase another game license?

Some of my search suggests that this can be done without having to purchase another license, I just need to create a new account for her. If so, what type of an account? A Microsoft account or a Minecraft account? And then how do we link it to the original purchase? Note, we did not create a Minecraft account when we purchased the game. We purchased it from Microsoft and downloaded it from there.

If the above is NOT possible and I do have to buy another game, then what about this…can I link the ipad Pocket Edition to the Windows 10 game so that my daughter can play on the ipad with her brother on the computer? I purchased the iPad version as well. They just don’t like it as much.

Not tech savvy and gaming is not my thing. So please help! Thank you!