You can stick something onto a human cell to reprogram its behavior

https://wyss.harvard.edu/news/a-backpack-full-of-multiple-sc...

Radical modifications of cell membranes have been a think for a while

https://en.wikipedia.org/wiki/Cyborg#Bacterial_cyborg_cells

and of course there is

https://en.wikipedia.org/wiki/Artificial_cell

and rapid advancement in synthetic biology.