Please follow the steps for successful installation & setup on the AWS EC2 Linux machine.

1. firstly need an instance for that AWS > EC2 > launch instance > give details and choose ubuntu as AMI

1. connect to your instance by selecting your instance > connect > connect

1. Now for installing Jenkins need to install JDK on any machine. let's install all packages one by one :

updating ubuntu system first : sudo apt update

Install Java using :sudo apt install openjdk-11-jre

Validate Installation : java -version

output should come like : 

openjdk version "11.0.12" 2021-07-20 OpenJDK Runtime Environment (build 11.0.12+7-post-Debian-2) OpenJDK 64-Bit Server VM (build 11.0.12+7-post-Debian-2, mixed mode, sharing)

1. Now let's install Jenkins :

curl -fsSL https://pkg.jenkins.io/debian/jenkins.io.key | sudo tee \   /usr/share/keyrings/jenkins-keyring.asc > /dev/null 

echo deb [signed-by=/usr/share/keyrings/jenkins-keyring.asc] \   https://pkg.jenkins.io/debian binary/ | sudo tee \   /etc/apt/sources.list.d/jenkins.list > /dev/null

sudo apt-get update 

sudo apt-get install jenkins

1. start Jenkins :

sudo systemctl enable jenkins

sudo systemctl start jenkins

sudo systemctl status jenkins

1. Open AWS EC2 > SELECT EC2 > select security group > inbound rules > edit inbound rules > add rule > CUSTOM TCP > PORT = 8080 > Done

1. let's open jenkins and set up :

as you can see check that directory for admin pwd using :

cd /var/lib/jenkins/secrets/initialAdminPassword

put prompt password and set up all details :

save & continue > install important gradle and plugins :

and here will be the Jenkins URL with port 8080 which is the default port in Jenkins :

click save & finish and you are good to go.