Generally speaking, yes. However, depending on the type of furniture you plan on using and its current condition, the level of effort required to convert it can be quite substantial. This is because you need to ensure that the furniture you want to convert into a humidor is tightly sealed and fully insulated.
Then, you need to purchase a humidity control system, a thermostat, and a hygrometer. You need all of these to make sure that the newly modified piece of furniture can maintain the optimal climate for storing your cigar collection.
In most cases, it's cheaper and a lot less hassle to invest in a purpose-built furniture humidor rather than trying to convert a piece of furniture into a humidor. Not only that, but your piece of furniture might not have the structural integrity or materials to effectively maintain the correct temperature and humidity inside.