First conditional

First Conditional

Hi Zoya, 

Just a few points to share with you, 

1. Your conditional sentence comprises a main clause (I'll ask for your help) and a subordinate (if) clause. When we write a subordinate clause before a main clause, we use a comma (,). The subordinate clause is "If I have any questions that I cannot figure out"; therefore, there is no need for a comma before the word "that". 

2. The words "can not" should be "cannot", which expresses the meaning of an inability. Of course, there are cases where "can not" is used commonly with "but also". Example: These green industries can not only create more jobs, but also promote sustainable development. The meaning of "can not" is not the same as "cannot".

3. When we use a modal verb (e.g. will), the main verb after the modal verb has to be in the simple present tense (e.g. ask)

Hope these help you. 

I would have said the following:

"I will ask you for your help if there are any questions which I do not understand".

I hope this helps

First conditional