Stupid question

I'm now convinced to jump "all-in" in XEQT. My question now is: Should I wait for any specific price drop to buy the ETF (~80k) or can I just buy it any any time?

Also, is XEQT the "best" (I know, "best" is very subjective) option regardless of the account? TFSA, FHSA, RRSP, Non-reg... Asking just to confirm as I watched a video where the person was investing in VXC instead of XEQT in their RRSP account. Why?

Last one: Does the dividend we get in our TFSA/RRSP/FHSA accounts consume from the contribution room, or only the contributions we make to them?

I'm new to investment (but I do understand the implications of investing 100% in equities), so I just want to make sure I'm not doing anything dumb (besides these questions 😂).

If there's anything else I should know let me know!

Thanks!