Do you mean you are in third year? Semesters mean there are two per year. I'm guessing you mean 3rd year, and not third semester, since that would mean middle of your second year.
You apply for electives depending on when you have time to do them and also depending on which type of elective you want to do. If you want to do a research elective, you can find those going on all throughout the year.
Some clinical electives also go on all throughout the year, but many of them have specific dates. If you have a winter or summer break that coincides with the dates of the school that is offering the clinical electives, then you can apply for those dates, and you should always start the process at least five months in advance.
There are hundreds of universities that will accept people for research/clinical electives, so I don't really know how to recommend one for you. Pick a field you want to go in and go from there.
Also, probably a good idea to read the thread which is specifically for electives here.
This thread here also tells which med schools in the US accept foreign students.
You apply for electives depending on when you have time to do them and also depending on which type of elective you want to do. If you want to do a research elective, you can find those going on all throughout the year.
Some clinical electives also go on all throughout the year, but many of them have specific dates. If you have a winter or summer break that coincides with the dates of the school that is offering the clinical electives, then you can apply for those dates, and you should always start the process at least five months in advance.
There are hundreds of universities that will accept people for research/clinical electives, so I don't really know how to recommend one for you. Pick a field you want to go in and go from there.
Also, probably a good idea to read the thread which is specifically for electives here.
This thread here also tells which med schools in the US accept foreign students.