Respected sir/madam,
It is most respectfully stated that, I have a general querry regarding about applying for dependent visa while staying in u.k,
Sir/madam, I just recently got married in u.k and my wife is also got the student visa from her back home country and she is curruntly studying in the university,I am also curruntly studying on a student visa,and my study is about to finish and visa as well.
My query is that,wheather I am eligible to apply for dependent stay to leave remain in uk on behalf of my wife,within my stay remaining in u.k before the expiry of my visa?or I have to leave u.k to go back my home country to reapply for the visa as a dependent?
We are also in this position to bear our all expenses,without taking any benefit or public funds form the government.
I would be very grateful to you for this kindness, if you give us your precious advise from your precious time.

With regards,

You can file for a "change of status" from student to student's dependent without leaving UK, but it does not mean you have a new "visa". So if you travel outside UK, you will need to re-apply for dependent visa from your home country, or you won't be allowed to return.