See example below.

data test;
    do x=0 to 2*constant('pi') by 0.01;
        sin=sin(x);
        cos=10*cos(x);
        output;
    end;
run;


symbol1 c=Blue v=none i=spline l=1;
symbol2 c=Red v=none i=spline;

proc gplot data=test ;
    plot sin*x / vref=0 lvref=2 href=0 lhref=2;
    plot2 cos*x /vref=0 lvref=2 ;
   
run;
quit;

Thanks！