If it is Class 2, set 1 dummy variables and assign them to 0 and1; There are three categories, and two dummy variables are set. Each of these two variables is assigned a value of 00 to represent one category, 0 1 to represent one category, and 1 1 to represent another category.

There can't be too many classified variables in the independent variables, otherwise the interaction will be enough for you to explain. As multivariate analysis of variance, multiple independent variables, 1 dependent variable.