It looks like you have a few problems here. The first is one of spelling. I think you might have spelled the names in your query wrong (studdet instead of student, adress instead of address, etc.) Check there first.
Next, it looks like the values you are inserting are variables but you are not properly escaping them from the string. This is how you should do it:
st.executeUpdate("INSERT INTO studdet ( NAME, EMAIL,phoneno,adress )values ('"+name+"','"+email+"',"+ph+",'"+ad+"')");
Notice the double-quotes to escape the string and allow the variable to be accessed properly.
As a side note, I would recommend that you not put variables directly into a SQL statement until you have first verified that they are "clean" (no special characters that could lead to a SQL Injection attack).