A fatal decision you can make as a website creator is to plan your website down to the smallest detail.
You cannot plan a tree. You can only plan to plant it in a favourable spot. You can't plan how to swim: but you can plan to learn to do it on a body of water where there are no three-metre-high waves and foul-tempered sharks.
A website accompanies you on the journey of your company's lifetime. You can plan its structure that allows for growth and you can plan the technology that allows for expansion.
But then you should get started. Because the experience you gain through mistakes and feedback is more valuable than a lengthy and usually frustrating planning phase that aims to be "perfect".
Have the courage to simply get started with your ideas.