In[]:=
​​InputField[Dynamic[g]]​​Dynamic[Show[{Plot[g,{x,0,10}],ListPlot[{0,1}]}]]
Out[]=
g
Out[]=
2
4
6
8
10
-1.0
-0.5
0.5
1.0
In[]:=
Dynamic[Show[{Plot[g,{x,0,10}],ListPlot[{Callout[0,"Hi"],1}]}]]
Out[]=
Hi
2
4
6
8
10
-1.0
-0.5
0.5
1.0