I had a Skype interview scheduled after I applied for an internship offer. However in the meantime, I received an internship offer, one of a kind I cannot refuse, and I wasn't much into the first offer anyway. As the company that proposed the second internship offer is a sponsor of my school, and is looking for numerous interns, and I currently am the first and only to apply, I am pretty sure to get the internship.
As english i not my native language, is it ok to use the Skype interview as "experience" to gain confidence, or is it unfair to the first company, who will spend some time interviewing someone who will not accept their its offer anyway ?