It is difficult to handle both of the kids alone at times.
Kids can definitely be tough to handle, especially more than one. Do you think they are extra difficult compared to your average kid?
They can be both stupid at time, they are lazy and the house is always a mess.
Don't be so hard on yourself since kids are never easy to handle. You are doing your best and it's okay to feel overwhelmed by them. If you weren't around to keep them in check, imagine what they will do.
I need to leave a powerful legacy anyway.
This is a pretty natural feeling you are having. Energetic kids can be stressful as you may always find yourself cleaning and reprimanding them. Just know that all the parenting you are doing will be worth it in the long run.