First, I commend you on your desire to improve.
Regardless of the second language, I believe one should always strive to speak at or near native level. I, certainly, would not want to learn Chinese or Russian, and then cause offence to those speakers by speaking their native tongue so poorly.
Secondly, might I suggest that English is your language too. And as a human being, you have as much right to learn to speak fluid and fluent English as any other native speaker.
So, I recommend that you practice English with a native speaker here on Italki. There are many wonderful tutors here, and English speaking countries span the globe. So, it doesn't matter what hour of the day or night. There are plenty of tutors here to help you.
there are tutors and teachers on Italki that specialise in interview preparation. I recommend you give one of them a try.
I don't recommend at this time movies or videos. English is a highly idiomatic language; we don't have special endings nouns or adjectives to indicate cases or gender. I would highly recommend that you find a tutor. A tv programme might just confuse you.