Hey dude, well fortunately you are in some luck here with YouTube; once again coming to the educational rescue having many tutorials floating around on the ue4 tower defense subject.
However, there is one person in particular with a dedicated series which very well could, plausibly, maybe, perhaps, possibly, presumably, probably, potentially, theoretically, get your core-game functionality nearly finalized.
Hope this helps!
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‘UE4 With Casey - Tower Defense Tutorial Series’
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