Why Tasks is soo hard to complete?

i have a question, how to make tasks not hard. Like taking a shower have a lot of steps and work or brushing my teeth or anything that is called basic and easy for people. Like brushing my teeth. It's like brushing my teeth:

1. Get out of bed

2. Grab my brush and toothpaste

3. Run the water

4. Put the brush underneath the water

and etc like it's too much for and i struggle with basic things like hygiene for years. Years. And then I get yelled at cause i'm still struggling with it like i have trying everything apps, planners, and nothing works. I can only do one task at a time but also depends on my energy levels. Any tips or advice.