Yes, I understand that I don’t need the categorical variable. The problem is that I couldn’t find a way of using structured data without having at least one categorical variable. The fastai library does not let me create a ColumnarModelData object without a categorical variable. I already asked this another topic but got no answers. So if you know about any better way to work with structured data I am all ears 
Bellow is the plot you mentioned. As we can see the loss is not decreasing, showing that no learning is tacking place. Regarding the learning rate I don’t understood why you mentioned it. I used the usual approach shown in the first 4 lessons of the course which is first using lr_find() to find an optimal learning rate. Since we cannot pick a learning rate from the plot I select 1e-3 once it seems to be a good choice for most general applications. Is there any erros in that approach?