Tool/software: TINA-TI or Spice Models
Hello,
there is already a thread about this and it is marked as resolved.
However, there is a better way and it works the same way as in LTSPICE or other Spice programs.
You select the model "Coupled Inductors (Spice)"
You get something that looks like a transformer at first sight, but it is not a transformer. You cannot connect wires to it.
Open Properties. There you can input a coupling factor and a list of inductors that you want to couple.
(You can only couple inductors which you have instantiated before)
It works the same way as in Spice.