I am on F1 status now for masters degree.
I completed a PAID internship (66 days) (within my field of study) in the Summer before graduation (undergrad) , I am realizing it was unauthorized because it was not under CPT.
Left the US after graduation, now I am back for grad school under new I-20 and sevis record. A company will start the h1b process for me soon.

Do I notify them of what happened?

Will I get automatically rejected?

Does the 245k apply to h1b?

Does the 180 day rule for unauthorized employment work under h1b?
I always worked on campus and this was my first internship. I never did CPT or OPT.