Hi, I would like to share my experience in case it might be helpful for other newbies (like me) around here.
I created a bigger NN model (nn.Module child class) containing 2 smaller subnetworks.
I just defined first the simple subnetwork as a nn.module child class.
Then in the init method definition of the bigger model class, I just called/defined the 2 submodels.
They appear of course also in the forward method (with same input x in my case).
You can then add another layer to merge the solutions coming from subnetworks, in case you need.
Training goes than as usual.