How do I cross-reference my Investments/ETFs to make sure there is not too much overlap in one sector? (I have no idea if my investments are balanced or heavily weighted toward Tech or finance, etc) *Also need to know how to cross-reference to make sure that my EFTs do not cancel each other out. (If there is a website link to do this, please share it + explain how to use)

The premium version of morningstar.ca gives me the portfolio tools you're looking for. And the digital subscription to the Globe gives me similar portfolio evaluation tools. I don't know anything free that'll give you what you want though. Morningstar.ca is the cheaper of the two. But the free stuff will take you pretty far on that site.