Although Minecraft's Java and Bedrock Editions are quite different, it's still possible to convert an existing Java world to Bedrock if you don't mind there being some differences to the world ...

How to Buy and Install Minecraft on (Almost) Anything: Where to Download, What Version, and More Punch a tree.

Here's how to download Minecraft snapshots, whether you're on Bedrock or Java edition so you can play future updates early.