Single word request for exercise book

I need the correct term for this one: https://en.wikipedia.org/wiki/Exercise_book#/media/File:Exercisebook.jpg

In the German language we just say "Heft". The English term seems to be "exercise book".

But "exercise" is just one aspect of this thing. I can write cooking recipes, my to-do list, my thoughts.

I do not EXERCISE in this thing!

The specific attributes for this thing are:

a) It has about 30 to 80 pages, so it does not need much space.
b) The "cover" is not solid, so I can bend it and it can't break that easy.
c) It is EMPTY at the beginning.
d) It is cheap.

My question is now: Is there another term for it, when I do not use it for school or exercise?

I need special help with the word "book" in "notebook": In the German language, when a thing has "Buch" in it, it is THICKER (more pages). Is this similar in the English language?

A notebook is the answer you're looking for.

A "journal" is a smallish, usually flexible-covered book of empty pages. It can be used as a diary to write one's thoughts but it can also be used for all the other things you mentioned.

A jotter, perhaps?

jotter noun [ C ] also jotter pad UK
​
a small book used for making notes in

Cambridge Dictionary