How many states when converting CFG to PDA
When converting CFG to NPDA ,then to simplify the process, first convert the CFG to Greibach Normal Form(GNF). Now using three states: Qstart, Qloop and Qaccept, you can generate all transition rules for the NPDA.

To start the process add the transition: $ δ(Qstart,λ,z)=\{(Qloop,Sz)\}$ where S start variable and z is stack start symbol.

And add the following transition to get the NPDA into a final state:$ δ(Qloop,λ,z)=\{(Qaccept,z)\}$.

Now using the production rules of the CFG you can easily generate all the other transitions which includes only $Qloop$. And here the number of transitions depend on the number of production rules.