Two Tables Join in display third table values in Gridview

I have 1 DB Students with 2 Tables Student & Course

Columns are

For Student       For Course

Sid                            Cid

Sname                      Cname

Joining Date                Fee

Finishing Date

Completed or Not

My problem is am create another Table STUENTCOURSE , i want save the combination of student and course values in third table (i.e, am enter Sname or Cname in front-end it display Sid, Sname, Cname, Fee, Joining Date, Finishing Date, Completed or Not.. in grid view).

I want retrieve values from third table display in grid view

My Front end Application is

Student Name TextBox

Course Name  TextBox 

Show Button 

One Grid View

If anybody understand my question plz reply...