Here I am just inserting two records you can insert as many as you want.
Add column to the student table (that is phone_no).
ALTERTABLE STUDENT ADD PHONE_NO NUMBER(10);
Modify the column name of phone_no to student_no.
ALTERTABLE STUDENT RENAMECOLUMN PHONE_NO TO STUDENT_NO;
Rename the table name to student_info.
ALTERTABLE STUDENT RENAMETO STUDENT_INFO;
Delete any records from the table.
DELETEFROM STUDENT_INFO WHERE STDID =2;
Note:- DBMS is not a strictly type language, meaning if you write in small letter or capital letter
it doesn't make any difference, It is good practice to write everything in capital letter.