Yes, you can use Office 365 on multiple devices. With a Microsoft 365 subscription, you can install and use apps like Word, Excel, and Outlook on PCs, Macs, tablets, and smartphones. Typically, a personal or family plan allows installation on multiple devices, though simultaneous sign-ins may have limits. To access Office 365 online, you can visit portalofficecom and sign in with your Microsoft account. This allows you to use web versions of Office apps, manage your subscription, and access cloud storage via OneDrive. Your documents sync across devices, ensuring seamless work from anywhere with an internet connection.