How can I make LEGO game

I wanted to make a LEGO game on unity but I dont know how to get LEGO bricks into unity and I would use blender to make LEGO bricks but I want to be able to actually get real bricks into my game but i dont know how to do it.

There would certainly would be copyright issues. You can read more here : LEGO FairPlay Guidelines.

That said, if you are doing this a personal product and intending to release it or infringe in anyway on LEGO’s IP, there are many ways to go about getting various LEGO parts into blender (and then Unity). You can use the LEGO Digital Designer to build models and export them to an ldraw format, and there are many tools that let you convert from that point. You may have to use use intermediate formats and tools depending on your OS and what you are going to do with them. There is plenty of info available on LDraw’s site.

However they are primary designed as a tool for prototyping LEGO models and share building instructions and things that nature. They were not intended to be used for games (well… actually LU worked closely with LDdraw and their work was used in LEGO Universe.). So generally speaking if you actually want to use them in a game or animate them, you will have to clean up the exported parts A LOT. They normals are usually off, ploys not actually connected, some parts incomplete or missing, etc. But worse case scenario, they are great for giving a great starting point and reference, even if you have to completely rebuild them using the exported assets as reference.

Hope that helps!