Just from curious how do you learn couple things?
Let say I would like to upgrade my skills from docker/Kubernetes/RedHat/Terraform.
what is your strategies, because for example I finished terraform first course here, it was massive amount of knowledge then I went to Kubernetes and 3 weeks later when I almost finish Kubernetes I think I forgot 50% from terraform 
Do you learning 3-4 things at one time and jump from topic to topic after 20-30mins or finish one course then go to another?