Before updating to a new version of Amazon Linux, I like to update apps installed on the EC2 instance, you are usually notified of new versions when you SSH to your EC2 instance and tell you which command to run.
Update Repos:
sudo yum update
Update Apps:
sudo yum full-upgrade (full-upgrade removes dependencies that are no longer needed)
Check which versions are available:
/usr/bin/dnf check-release-update
This will give you a list of available versions:
sudo dnf upgrade --releasever=versionhere
Reboot for good measure
sudo reboot