As long as you are aware of the fact (I assume everyone does) that it is tourist central and hence not that blessed with eat/drinkeries that strike a balance between 'nice' and 'not packed to the gills', I would recommend Lowlander on Drury Lane to get your Belgian beer on.
It will be packed though.
Failing that, The Lamb and Flag is a great spit and polish proper pub.
It will also be packed.
Both 2 mins from Covent Garden station.
Failing that, just hit a chain. You know what you will get.
Avoid Wahacca. Ridiculous wait times cos its trendy like. And it's dead average.
Meat market is ok, but now too popular and hence not worth the interminable wait
If you can spare the time to jump the tube and go pretty much anywhere else away from the throngs, I couldn't recommend it enough!
Joe's in Covent Garden does very nice fried chicken, although they don't sell all their burgers past 6ish, which is a bit odd in my opinion. Always had a nice time there though, and has quite a long bar area so you could conceivably just pop in for a drink. There's a nice pub I go after training which I think is called The Globe, they have a good selection of ales.
I don't know how well you know that area, but it's incredibly close to a lot of other stations/areas. When I train there I get the Tube to Charing Cross, which is in turn really closer to Leicester Square. In the other direction you're really close to Holborn, which has a lot of good coffee shops because it's a big legal firm/office area.
There are quite a lot of chains in the area, but Paul's is nice and a bit unusual (I don't recall seeing them outside London). There's also Crusshh, which is right by Charing Cross and is more of a juice bar style coffee shop. I never see it busy, I'm usually there at about 6.