can't attack from compendium even though I bought MM, VG & Mordenkainen's ToF. Not getting monster sheet to open for me

I bought the MM, Volo's Guide and Mordenkainen's Tome of Foes and when I search for "orc" or "goblin" I don't get anything that I can attack from. All I can do is drop a token onto the screen or click on the monster name to open up a popup that describes the monster in detail, but there is no sheet with Bio/Character-Sheet/Attribute tabs where I can attack from. I've scoured the popup sheet, which is basically a description of the monster, but there is nothing I can click on that results in an attack. If I click on a weapon like "short bow" it takes me to another item description. Any idea what's up?

It sounds like you're on the Bio & Info tab instead of the Character Sheet tab. Once you drag a token onto the map from a Compendium monster entry, you should get its character sheet appear in your Journal. You can access the NPC character sheet from there, or you can alt-double click the token on the canvas to achieve the same (provided it is linked to the sheet... it should be if it's from the Compendium). You can't use anything directly from the Compendium - it needs to be in the Journal tab before it's actually part of your game, and can be used to roll dice, track Attributes and so forth. If you're still having dramas, post back with a screenshot of what you're seeing.

SONOFABITCH! That's what I was missing!!! THANK YOU sooo much. I knew that I was able to call up all the correct info before, but haven't done it in a while, since I use monsters on DNDBeyond. I just forgot about the connection between the journal and the compendium. Thanks again! Back to Storm King's Thunder.