How high is the temp? Honestly I'd just monitor it and make sure he's getting fluids and rest. I avoid treating fevers unless they get too high or they're very uncomfortable and not eating/drinking. The fever is their body's natural response to fight whatever's wrong, keeping it down can actually prolong being sick. Meds can also mask other symptoms

Put it in they drink

I mix it in my children drinks

If it helps, my kids only like the grape flavor of all the medicines (Motrin, Tylenol)

If the medicine is liquid form give him a little bit of juice with the medicine in it.v without him knowing the medicine is in it

Cool bath helps too and a wet towel on the neck and feet , sit him on the counter and make him take the medicine

Put the medicine in something he will eat. Or use one of those syringe type things for smaller kids and hold his head back and squirt it in the side of his mouth real quick...that one really works