Get free access to Word, Excel, and PowerPoint using Microsoft 365 for the web (formerly Office)
A free Google account gives you access to:
amongst other tools
Zoom is a communications platform used for virtual video and audio conferencing, but also allows live chats, screen-sharing, and other collaborative options. Zoom Basic accounts can be created for free.
Webex offers a free plan that allows users to participate in meetings and utilize basic collaboration features.This free plan provides access to features like unlimited 1:1 and team messaging, screen sharing, and whiteboard functionality.