I use number of formats depending of students' choices and their own preferences. Usually, if its online, I use Zoom and also screen sharing containing PDF books, whiteboards etc. Also provide, if platform permits/company permits, direct WhatsApp number to facilitate video call to explain subject or topic issues when needed. Home works/courseworks can be used to teach or check/provide comments using Microsoft Words or Google Teams (or Apple's Pages) interactive sharing facility to comment/edit. Occasionally or even regularly - company's/platform's terms and regulations permitting - onsite/offline meet ups in libraries or coffee shops is available for students who prefer face to face teaching or guidance.