Are minecraft PE servers the same as the ones on Java minecraft?

No.

Java and PE can't play with each other because they both run their own edition.

Java = Java Edition

PE = Bedrock Edition

The Java edition has snapshots and the most recent updates, which is why the Bedrock Edition updates are delayed.

The Bedrock Edition has a cross play feature, allowing Windows 10, Xbox One, iOS, Android and Nintendo Switch to play together.

Sorry to note that the formerly named "Portable Edition" (now just called "Minecraft") runs on the Bedrock Engine, which runs separately than the Java Edition.

With that said, all devices that are running on the Bedrock Engine (Windows 10, XBox One, Nintendo Switch & Mobile) have cross-platform support… So you can play with others, even though they may be running a different platform.