[CFD Flow]

Hi guys, I am relatively new to CFD and Ansys Fluent.
I am trying to create a model to mix two different miscible, incompressible fluids together in a T-piece.
The solvents are THF (tetrahydrofurans, 980.9 kg/m3, 0.00185 kg/m/s) and Et2O (diethyl ether, 809.2 kg/m3, 0.000845 kg/m/s) at -70°C.
The flow is laminar Re<10
The condition is steady-state

I would select the following parameters:
Type --> Pressure based
Time --> Steady
Energy -- > On
Viscous --> Laminar
Model --> Species transport

From here on I do not get any further. I don't know which properties to insert in the mixture template so that the density and the viscosity of the mixture fluid can be calculated in each point depending on the volume fraction of THF. In the publication I am trying to reproduce, a UDF was used for this. Can someone help me from here on to solve the problem?
The paper I am trying to reproduce the model from is: Science 2016, 352, 691, DOI: 10.1126/science.aaf1389

I appreciate any help!