To perform a two-way ANOVA in Minitab, use Stat > ANOVA > General Linear Model > Fit General Linear Model. Suppose your response is called A and your factors are B and C.
Choose Stat > ANOVA > General Linear Model > Fit General Linear Model.
In Responses, enter A.
In Factors, enter B C.
Click Model.
In Factors and covariates, select both B and C. To the right of Interactions through order, choose 2 and click Add.