Dear Suman,
thank you for this question, this is easy to do in Morpheus. I attach such a model (xml) which you can open in the Morpheus-GUI to inspect and change all aspects.
There are two cell types (besides medium): cell_secreting (which secretes U with flux p into the Global/Field U.external) and cell_receiving (which takes U up from U.external with rate d and accumulates it in U.internal, when U.internal exceeds U.threshold=500 then cell_receiving changes its state U.superthreshold from 0 to 1). The chosen CPM settings let cells of different types repel each other and let cell_receiving chemotax upward the U.external gradient.
The attached figure shows an intermediate state where U.external is shown on a white-yellow-red scale with isolines in the background. Receiving cells are color-coded by their U.internal as given by the color bar. The number (0 or 1) in each receiving cell is the state of U.superthreshold.
You can extend that model by different motility modes and by new cell behavior once U.superthreshold has switched to 1. Also the field U.external may get extra reaction terms (for an example see:
https://identifiers.org/morpheus/M0012).
Best,
Lutz