I am sorry to hear your little pup has bit of a cough at the moment… It would certainly be a good idea to take him down to your local vet to be examined, and undoubtedly cuddled while he is there! It can be helpful to get a video of the coughing if you can as well.
The first thing we need to establish is that he does have a cough, and not retching for example. The most common cause of coughing in puppies is “Kennel Cough”, which is an umbrella term for lots of infectious viruses and bacteria that cause tracheobronchitis, an infection of the upper airways. Puppies can also be at risk of developing secondary pneumonia in more severe cases.
If it turns out he does have “Kennel Cough”, he may require home nursing care and possibly antibiotics, so it is important to be assessed by a vet. We want to get your little sausage back to being 100% again. There are also other causes of coughing that may require further investigation.
I hope you and your vet can get his cough resolved soon, so that your darling Cavoodle is fit as a fiddle again!