How to remove unnecessary items

My company provides services and does not sell products. How can I delete items that we don’t need in the form of an account? I highlighted them in red on the image.
Also, how can I remove the selection of prodacts from the invoice form? I turned off the products module, but this does not help. In the image I marked it in green.

Your answer is not entirely clear. Is this all impossible in CE configuration?
For us, the most important thing is to remove what is highlighted in green in the picture ...

I understood you. Is there any kind of template editing tool? Unfortunately, not everything can be done through the configuration of modules.