https://www.edutopia.org/article/how-use-5es-remote-math-instruction
This is an outstanding article from Edutopia about the benefits of the 5Es instructional model, although it doesn’t address a lot of the specific difficulties in adapting this model to remote instruction.
It suggests, for example, dragging and dropping clipart on a Google Slides presentation to simulate the physical manipulation of objects in the classroom. I question the extent to which this is a substitute for physical manipulation and the engagement that results, although any interaction is better than none.
There are two good links to activity websites: Desmos, which offers a good range of algebra and geometry activities, with a section curated for British GCSE Maths, and Open Middle.