You can plan ahead but usually thats more of planning around possible disruption/permission than actually achieving a desired position/board state/etc. Such as playing around a hypothetical Daze/Spell Pierce, playing an SFM before your opponent has a chance to Thoughtseize, playing out creatures you want to eat spot removal before you can safely drop the creature you want, dropping your Karakas early when you know the opponent plays Wasteland that way you can safely play the 2nd one and the dual you have in hand...

So really it depends on if you're referring to a 'plan' as a strategy or as a tactic. I think, in general, your game plan is your deck strategy and you generally plan your deck around achieving a soft/hard lock like in Lands/Enchantress, a clock like in aggro, a combo turn where you win, or a synergy that will give you a superior board state. I'd say tactics are short range plans. You usually have to decipher the opponent based on the matchup and potential deck list variations and then plan around what you know about the opponent's archetype. But usually you don't just plan one tactic at a time. You have to, for example, play around Daze but make sure you have mana to cantrip because there is a creature on board and you want a removal spell. Then sometimes your tactics clash and you have two different routes to go based on the mana. Then, all of a sudden the plans you were just making change completely because you cantrip into something really good or something really bad. Like Ponder into 3 lands? There goes that plan, shuffle library, draw a card. Oh wow an extra spot removal when I wanted a creature.

Even within the turn there's a constant process of planning and replanning. This isn't chess. In chess, you can plan ahead because only one piece moves during a turn. In magic, each turn has so many moving parts that you can have a general game plan and general plans for how to interact with your opponent.. but sometimes the opponents strategy trumps your strategy and all of a sudden you can't really play your strategy anymore. Take Dredge as an example. Most decks don't just have maindeck resources sitting around that are really good against Dredge. Usually you have to board in hate, and then all of a sudden your plan is to hate the graveyard centric strategy while Dredge's game plan is now to outmaneuver your hate plan. So then you have to execute your own strategy in time before Dredge can start shitting Zombies on your face.

Also.. there are decks like Belcher and Burn. Where thinking turns ahead is.. "hmm should I swing with ALL of my goblin tokens now? Or swing with HALF just to prolong my opponents imminent demise to reiterate the fact that I don't really want to play magic?" or... "FUCK! Should I play this Lightning Bolt right now? or this Chain Lightning? or this Lava Spike? God damn it WHY IS MY LIFE SO HARD!? I should have brought Belcher..."