IS thinking what kind of noun
Your question is a bit unclear. Do you mean "What kind of a noun is thinking"?IS thinking what kind of noun
Thinking could either be a verb or a noun. For example:
Tom is thinking very hard about the problem.
Here, thinking is a verb in its -ing form (present participle) used to form the present continuous verb tense (BE + thinking).
It can also be a noun. For example:
Thinking is difficult for Tom.
Here, thinking is a noun. It is the subject of the sentence. When the -ing form of a verb functions like a noun, it can be referred to as a gerund.
If this is not what your question is about, then I have no clue what you mean.