The modified Levene's test uses the absolute deviation of the observations in each treatment from the treatment median. It then assesses whether or not the mean of these deviations are equal for all treatments. If the mean deviations are equal, the variances of the observations in all treatments will be the same. The test statistic for Levene's test is the ANOVA F-statistic for testing equality of means applied to the absolute deviations.
You can do this in Minitab by making a new column where each value is the absolute value of the response minus the median of that treatment. Then perform a One-Way ANOVA using the new column as the response. The F-statistic and p-value will be the test statistic and p-value for Levene's test.
For example, suppose the responses are in C1 and the treatments are in C2, and C3-C6 are empty.
When you examine the output you see that the F-statistic and p-value in the One-way ANOVA table are identical with the test statistic and p-value for Levene’s test.