To transition from a Citrix Admin to the Cloud domain, you'll need skills in cloud computing concepts, major cloud platforms (AWS, Azure, GCP), cloud infrastructure deployment and management, automation tools (Terraform, Ansible), and familiarity with containers, serverless computing, and cloud-native application development.
If you are interested in pursuing a career in cloud domain then I would recommend you to take up this azure online course from Intellipaat. This program provides you with all the required skills to switch your career.
Along with that do check out this video on how KiranKumar achieved a career transition from a citrix admin to a cloud team lead with the help of Intellipaat training -