What's the meaning of 'would be donging' For example, You would be using English in this job. Can I say, You will use English in this job.

How to use the word "would"? And what's the meaning with different usage?

In this sentence"It's like something out of movie",can i use "in" to replace"out of"?

Is there any difference between past tense and present perfect tense? Example: I ate an apple, I have eaten an apple