Getting started with the new ARM based M1 Macs can be a bit awkward so here is how you get Maven working with JDK 8.

Install Homebrew

Homebrew is what we will use to install Maven. You can instructions on downloading Brew here https://brew.sh/ or by simply running this script in your terminal

/bin/bash -c "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/HEAD/install.sh)"

Install Maven via Homebrew

Run the following command in your terminal

brew install maven

Install ARM based JDK 8 from Azul

We need to get a version of JDK 8 that works on the ARM based M1 Mac, Azul provide just what we need. At the link below, enter the following if the link doesn't populate it for you.

Java Version - Java 8 (LTS)
Operating System - macOS
Architecture - ARM 64-bit
Java Package - JDK

Download the .dmg file here
https://www.azul.com/downloads/?version=java-8-lts&os=macos&architecture=arm-64-bit&package=jdk

Install the .dmg file

Set JAVA_HOME environment variable

Now you need to set the JAVA_HOME environment variable to point at our new JDK 8 install. This is the environment variable that Maven looks for.
To add the environment variable, you need to add it to your zsh profile. This can be done by adding the following line to your .zshrc file.
The .zshrc file should be located in home directory.
You can navigate to it via

# Navigate to directory
cd ~
# Editing the file
vim .zshrc

Add the following line to the file and then save

export JAVA_HOME=/Library/Java/JavaVirtualMachines/zulu-8.jdk/Contents/Home/jre

Now restart your terminal

That's it!

When running Maven from your terminal then now it will use JDK8