Start learning the below tools with good practice.
OS: Linux (Rhel/Ubuntu)
Cloud: Pick one first like AWS (Amazon) learn it well then move to other Azure, Google & Openstack cloud
Programming/scripting: Bash n python
Orchestration: Terraform
Configuration Management: Ansible/Chef/Puppet. Learning process same as cloud pick one learn n then move to next one.
Containers: Docker, Kubernetes
CI/CD: Jenkins
Repository: Github/Git
DataStore: Sql (postgress) & nosql (Mongodb/Redis)
Last but not least learn apache/tomcat or both.
Learning above tools/technologies will transition you to DevOps/Cloud profile.
Udemy Courses:
JENKINS
https://www.udemy.com/working-with-jenkins/
https://www.udemy.com/jenkins-beginner-tutorial-step-by-step/
https://www.udemy.com/jenkins-quick-start/
https://www.udemy.com/jenkins-devops-pipeline-as-code/
https://www.udemy.com/devops-crash-course-cicd-with-jenkins-pipelines-groovy-dsl/
https://www.udemy.com/jenkins-intro/
ANSIBLE
https://www.udemy.com/ansible-essentials-simplicity-in-automation/
https://www.udemy.com/ansible-quick-start/
https://www.udemy.com/devops-series-server-automation-using-ansible/
https://www.udemy.com/devops-beginners-guide-to-automation-with-ansible/
https://www.udemy.com/just-enough-ansible/
GIT
https://www.udemy.com/git-started-with-github/
https://www.udemy.com/learngit/
https://www.udemy.com/git-expert-4-hours/
https://www.udemy.com/git-and-github-crash-course-creating-a-repository-from-scratch/
https://www.udemy.com/git-and-github-step-by-step-for-beginners/
https://www.udemy.com/intro-to-git/
https://www.udemy.com/short-and-sweet-get-started-with-git-and-github-right-now/
https://www.udemy.com/the-ultimate-git-5-day-challenge/
https://www.udemy.com/git-quick-start/
https://www.udemy.com/gitandgithub/
https://www.udemy.com/git-basics/
https://www.udemy.com/git-bash/
MAVEN
https://www.udemy.com/maven-quick-start/
DevOPS
https://www.udemy.com/learn-devops/
https://www.udemy.com/devops-for-operations/
https://www.udemy.com/linux-academy-devops-essentials/
https://www.udemy.com/learn-devops-kubernetes-deployment-by-kops-and-terraform/
https://www.udemy.com/devops-series-setup-environment-using-virtual-machines/
AWS
https://www.udemy.com/aws-essentials/
https://www.udemy.com/aws-concepts/
https://www.udemy.com/aws-certified-solutions-architect-associate-in-30-days/
https://www.udemy.com/cloud-computing-with-amazon-web-services-part-1/
https://www.udemy.com/learn-amazon-web-services-the-complete-introduction/
https://www.udemy.com/amazon-web-services-aws-v/
https://www.udemy.com/amazon-web-services-aws/
https://www.udemy.com/introduction-to-aws-cloud-computing/
https://www.udemy.com/mastering-aws-featuring-iam/
https://www.udemy.com/namrata-h-shah-aws-tutorials-dynamodb-and-database-migration-service/
https://www.udemy.com/linux-academy-aws-essentials-2019/
https://www.udemy.com/aws-get-started-with-load-balancing-and-auto-scaling-groups/
https://www.udemy.com/aws-certified-associate-exam-vpc-security-group-nacl/
https://www.udemy.com/getting-started-with-amazon-web-services/
https://www.udemy.com/amazon-web-services-aws-ec2-an-introduction/
https://www.udemy.com/introduction-to-serverless-aws/
https://www.udemy.com/amazon-web-services-aws-cloudformation/
https://www.udemy.com/introduction-to-cloud-amazon-web-services-ec2-instance/
https://www.udemy.com/aws-redshift/