When doing tuition online, it is important that the tutor can see working out regularly. The best tool for facilitating this is a graphics tablet.
Above is the graphics tablet I use: click the picture to find it on Amazon. I am not sponsored by Gaomon, nor do I claim that it is a particularly good, or even good value, graphics tablet: it is the only one I've used. But I can confirm that it is more than adequate for all tasks in tuition, and it is inexpensive. Suitable software for use with graphics tablets includes Microsoft Whiteboard and Microsoft Edge. It is worth students familiarising themselves with their use to benefit most from tuition.