Learning two engines at once

Is it feasible to learn two engines at once?

I can dedicate 1 hour to each. And go crazy on weekends

Some people say learning two engines isn't good, but then I thought how do we balance multiple subjects in school. I get it, now we have work and all, but 2 engines is like two subjects

I can make the time for it, but I just want to know if it's feasible in terms of the human brain to learn two engines at the same time efficiently