Depends on a lot of factors.
Some people are killed by the explosion or by objects hitting them as a result of the explosion.
If there is a rapid deceleration (eg the front being blown off) then people can have their necks snapped.
Depending on altitude there will also be the effect of de-pressurisation resulting in asphyxiation but it depends on the person and how fast the plane/person descends to denser air as to whether this kills them.
If the plane somehow keeps on flying and is not fully breached then smoke might be an issue but there would normally be a hole from an explosion.
If the plane keeps flying at altitude with a hole then asphyxiation is most likely.
If the plane is decending/falling then those initially unconscious from the de pressurisation may regain conciousness and be concious at the point of impact. But it is unlikely they will be fully concious or coherent, thankfully, but I am sure it does happen.
On impact with the ground it is the deceleration that normally gets you. Or if the impact is somehow softened then the next in line to get you is probably penetration of your body/head by a bit of the plane or luggage.
If still not that then you will probably be trapped with severe injuries and die from smoke, fire, punctured lungs etc. Or you might land on water and drown.
Going back up to altitude there is also the risk of you leaving the plane and in which case it again depends on altitude but you might initially pass out and then regain conciousness before hitting the ground or you might end up inside an engine or hitting the rear empennage.
Lots and lots of ways and sorry if it offends the more sensitive. Unfortunately I think one of the most likely in a large modern aircraft is you die from the rapid deceleration from hitting the ground, whether you are concious at the point I can’t say but there has been a fair amount of evidence of smoke inhalation suggesting people have still been breathing during the decent.
Basically just imagine a Final Desintaiton film and that is what is going on inside a plane that doesnt fully blow up as people are dying in different and pretty horrific ways.
(sorry again to those of a sensitive nature or have been personally affected by such things)