Analysis of covariance (ANCOVA) for Split plot Design

[#1]

Hi, I have a problem where I want to do ANCOVA and It is new for me.

We have,

1. Main plot data (2 treatments)
2. Subplot data (10 treatments)
3. Yield data

we want to add lodging (%) score as a covariate. How to do it? (I have seen some video tutorial from Youtube but its not easy to understand for me) Your cooperation will be highly appreciated.