Read the data from your user - that's trivial, you know how to do that.
Then:
using (SqlConnection con = new SqlConnection(strConnect))
{
con.Open();
using (SqlCommand cmd = new SqlCommand("INSERT INTO myTable (myColumn1, myColumn2) VALUES (@C1, @C2)", con))
{
cmd.Parameters.AddWithValue("@C1", myValueForColumn1);
cmd.Parameters.AddWithValue("@C2", myValueForColumn2);
cmd.ExecuteNonQuery();
}
}