Finding the Workstation Block for a Modded Profession
Identify the Profession First
Modded packs add professions that vanilla players have never seen. To find the right workstation, start by opening the profession's JEI page: hover an emerald or villager spawn egg and press the JEI recipe key (default U), then locate the profession you care about.
Get the Workstation Details
On the profession page, Just Enough Professions shows the name of the workstation block and a picture of how it looks. Write down or remember both. The name is what you'll search for in JEI; the picture is what you'll look for in the world or in the creative inventory.
Next, search that block name in the JEI search bar. JEI will show you the block's recipe (if it has one) so you know what materials to gather. If the block has no recipe, it may be obtained another way — check the mod that owns it.
Place and Test
If the villager claims it, its profession will change to match the page you looked up. If it doesn't, double-check that the block matches the one shown on the profession page — similar-looking workstations from different mods can be easy to confuse.