I am wondering whether or not I can build my own bike. I was thinking of buying some steel lugs or maybe carbon ones or whatever off the internet, and a steerer tube too, and was hoping I could connect them all with bamboo? Like sliding bamboo into lugs basically. Is this something I can do with very minimal effort or will it still be very hard?
You can't build any bike with minimal effort. Not even a toy one out of Lego. It would be faster and easier to get a minimum-wage job and save money to buy a commercially made bamboo bike. But a lot less interesting, and also less fun.
Turning bamboo into something suitable for a bike frame is quite a lot of work, and if you haven't worked with structural bamboo before you will need to do quite a bit of research before you start.
It would probably be easier to start by building a lugged frame from steel to get an idea of what's involved, then build a second copy of that frame using whatever bamboo you have available. See how rideable it is, and decided whether you want to continue down that path and eventually end up with a decent bike.