Lump or charcoal and wood chunks

I usually use Stubb's all natural briquets unless I get a good deal on other coals. Used lump once but it burned up really fast so I stick with Stubb's and add chunks of wood that I burn (char) in the chimney as I start more coals.
I get my hickory at Lowes but cherry and apple near a local orchard. They usually have great deals on seasoned wood.

It's hard to say what's "best." I think most guys with offsets like lump, or even splits of wood. Using charcoal isn't going to be bad either. Since you're new, my personal recommendation would be to start with name brand charcoal, Kingsford, Royal oak, etc..... Get a few cooks and some confidence going, then start experimenting with lump. The reason is that briquettes burn much more evenly, so are easier for a newbi to handle.

YMMV

I have a CG & I use briquettes & wood chunks & have no problem keeping stable temps for long smokes. I fill a Charbroil shaker basket with unlit with 3 large or 6 medium wood chunks mixed in. I leave enough room in one corner for about a half chimney of lit briquettes. Below is a pic of my basket before adding the lit from my last cook. I don't use lump. It burns too hot & too fast for my liking.

In my chargriller , I use mostly lump charcoal ( 100% hardwood turned into charcoal with no fillers added ) I add a wood chunk or two or three over the course of the smoke to add a little flavor as it goes. The lump is hardwood ( RO usually ) and gives some flavor as is. I toss a few wood chunks ( hickory , apple , mesquite , cherry birch ,...whatever I'm using ) on my chimney starter and give them at least a pre toast before I add them to the fire box.
That is what works best FOR ME .
Some have the best results with a handfull of chips wrapped in foil , some work the cold chunks into the coal bed , and some have learned how to actually keep a small clean burning fire going in that sfb using only splits and sticks of wood.
As you do more cooks you will learn what works best for you .
I've bought bags of chunks from home dumpo and lows . Also , any neighbors or freinds with fruit trees are a great source of wood . just season the wood and enjoy the TBS !