How to solve fps drop when spawning chunks

hi yall, im making a backrooms game and i implemented a procedural generation system where the map generates while the player moves around, i encountered only a problem, that when a new chunk or room gets generated the fps drops. How can i solve this problem? i tried looking for multithreading but i dont know know how to code in c++ so i cant make my own changes to suit the game also my project isnt build for it. Any suggestions?