You can install and use Dolibarr as a standalone application, or online on a shared or dedicated server or virtual machine to use it from anywhere, any desktop, tablet or smartphone. It is available in various forms: From auto-installer packages that install Dolibarr and all prerequisites with no need of technical knowledge, of from the standard distribution working on all Operating System platforms and PHP architecture (Windows, Mac, Linux). Dolibarr is of course available as SaaS application on ready to use Cloud services.
Because it's Open Source software, you can rely on the Open Source company of your choice to assist you or make custom development if you need so.