Linux is all about files and Dwija learning platform has a stunning course setup for this.
DevOps deals with Git, Jenkins, Ansible, Docker, Kubernetes, ELK, Terraform
Ansible is configuration management tool which can also be used for creating and deploying architecture. An indispensible tool for a DevOps Engineer
Docker is a container service which is basically used for provide Proof Of Concept. Easy to deploy architecture and deploy products within no time.
Kubernetes or k8s is docker orchestration manager which helps to deploy a product very quickly with features like Loadbalancing and Autoscaling.