3 to 6 days/week?

At the moment I'm doing intermediate large load program from the app, but training days are way too long. It takes me more than 3h to finish each workout. Is it bad to make from 3 days/week to 6 days/week and do something like this?

Monday, wednesday and friday: All the lowerbody work (squats, deadlifts and accesories)
Tuesday, thursday and saturday: All the bench work and accesories

Also, how much am I supposed to rest between sets?

Thanks for the help

That's doable.

Rest as much as needed between sets so that you can maintain quality reps. You don't have to race through it but you also don't have to try and recover 100% between sets either.

That's doable.

Rest as much as needed between sets so that you can maintain quality reps. You don't have to race through it but you also don't have to try and recover 100% between sets either.

Would it be a good idea to monitor your heartrate at first to determine how low your BP should be for a quality set, and then instead of "x minutes rest", just monitor your BP and start the next set once its under that amount ?

I'm considering this. When you have a good day, you should require less time between sets. It would keep the intensity the same

No. Don't bring heart rate into the equation. That's a totally different world of training.