Honestly, the answer of how they bring the symbiote into Spidey's life in the MCU is obvious. They do an almost comics accurate approach and bring it in during Secret Wars, provided the movie tries to capture the essence of the original 80s series. He gets the suit, doesn't realize it as anything in the movie but an amazing costume, and the Venom storyline can be dealt with in Spiderman 5. Clean and easy.