Hi @MH3 ,
Please refer to the ServiceNow site: https://www.servicenow.com/success/playbook/innovate-at-scale.html
In relation to installation, onPrem, PaaS... I would you to talk to a ServiceNow Sales rep, as this is very much specific to the single company requirements.
If my answer has helped with your question, please mark my answer as accepted solution and give a thumb up.
best regards
Anders
