Do guinea pigs make croaking and chirping sounds?

Yes!

Guinea pigs have a whole plethora of vocal noises. Some are slightly more obvious than others and can have a reason for them. Squeaking is most often about excitement, for example the anticipation of getting a tasty food treat. If they make a low chirping noise often referred to as a purr it can mean that they feel threatened or frightened. Very much depends on their body language as well as the noise, if you are trying to establish why they are making that sound.