Add installation and usage to readme

Signed-off-by: Stefan Prodan <[email protected]>

README.md

@@ -1,2 +1,73 @@
 # flux-operator
-Flux CD Operator
+
+[![e2e](https://github.com/controlplaneio-fluxcd/flux-operator/actions/workflows/e2e.yaml/badge.svg)](https://github.com/controlplaneio-fluxcd/flux-operator/actions/workflows/e2e.yaml)
+
+The Flux Operator is a Kubernetes CRD controller that manages
+the lifecycle of the [Flux CD](https://fluxcd.io) distribution.
+
+> [!IMPORTANT]
+> Note that this project in under active development.
+> The APIs may change in a backwards incompatible manner.
+
+## Features
+
+- Provide a declarative API for the installation and upgrade of CNCF Flux and the [ControlPlane enterprise distribution](https://github.com/controlplaneio-fluxcd/distribution).
+- Automate patching for hotfixes and CVEs affecting the Flux controllers container images.
+- Provide first-class support for OpenShift, Azure, AWS, GCP and other marketplaces.
+- Simplify the configuration of multi-tenancy lockdown on shared Kubernetes clusters.
+- Provide a security-first approach to the Flux deployment and FIPS compliance.
+- Incorporate best practices for running Flux at scale with persistent storage, sharding and horizontal scaling.
+- Manage the update of Flux custom resources and prevent disruption during the upgrade process.
+- Facilitate a clean uninstall and reinstall process without affecting the Flux-managed workloads.
+
+## Installation
+
+The Flux Operator can be installed using the Kubernetes manifests published on the releases page:
+
+```shell
+kubectl apply -f https://github.com/controlplaneio-fluxcd/flux-operator/releases/latest/download/install.yaml
+```
+
+## Usage
+
+The Flux Operator comes with a Kubernetes CRD called `FluxInstance`. A single custom resource of this kind
+can exist in a Kubernetes cluster with the name `flux` that must be created in the same
+namespace where the operator is deployed.
+
+The following is an example of a `FluxInstance` custom resource:
+
+```yaml
+apiVersion: fluxcd.controlplane.io/v1
+kind: FluxInstance
+metadata:
+  name: flux
+  namespace: flux-system
+spec:
+  distribution:
+    version: "2.x"
+    registry: "ghcr.io/fluxcd"
+  components:
+    - source-controller
+    - kustomize-controller
+    - helm-controller
+    - notification-controller
+    - image-reflector-controller
+    - image-automation-controller
+  cluster:
+    type: openshift
+    multitenant: false
+    networkPolicy: true
+    domain: "cluster.local"
+  kustomize:
+    patches:
+      - target:
+          kind: Deployment
+          labelSelector: "app.kubernetes.io/component in (kustomize-controller, helm-controller)"
+        patch: |
+          - op: add
+            path: /spec/template/spec/containers/0/args/-
+            value: --concurrent=10
+          - op: add
+            path: /spec/template/spec/containers/0/args/-
+            value: --requeue-dependency=10s
+```