Oracle plsql syntax confusion?

declare
    v_name varchar2(10) := 'bruce';
    v_name2 number;

begin
        case v_name
              when 'bruce' then DBMS_OUTPUT.PUT_LINE('corr');
              else DBMS_OUTPUT.PUT_LINE('incorrect');
        end case;
        DBMS_OUTPUT.PUT_LINE(v_name2);
end;




declare
    v_name varchar2(10) := 'bruce';
    num number(2) := 10;
begin
        num := case v_name
              when 'bruce' then 2
              else 12
        end;
        DBMS_OUTPUT.PUT_LINE(num);
end;

Getting confuse about semi colons. why in first code semicolon required and end case; keyword needed. But in 2nd code no semicolon & also just end; I know in 2nd I am assigning value to variable, but so what ?

case statement vs. case expression.

The case statement is for conditional execution of PL/SQL code:

    case v_name
          when 'bruce' then DBMS_OUTPUT.PUT_LINE('corr');
          else DBMS_OUTPUT.PUT_LINE('incorrect');
    end case;

The case expression can be used both in PL/SQL and in regular SQL, and returns a value:

    num := case v_name
           when 'bruce' then 2
           else 12
           end;