TLDR

1a. Check that your Openstack has all required modules, you will need admin level access **
1b. Check that you have an Azure subscription and an AAD where you have admin level (cost around 50 Euros per month) **
2. Create an AzureDevOps organization and create a private repo
3. Fork this repo as a submodule
4. Manually create Public DNS and build-agent tenants as well as a bootstrap keyvault
5. Copy the templates folder from the submodule into the root folder and fill out the variables

** you can obviously rewrite everything for different CSPs, but if you want 1:1 the same and minimal setup time, follow this tutorial