I just started watching EastEnders and I’m just wondering how I can watch older episodes if I can? YouTube is very limited to what is on there plus I’m from Australia so certain sites and stuff won’t work...
You can use VPNs to view certain sites. I don't know if you have done this already. You can use a VPN to access the BBC iPlayer website, where you can view EastEnders episodes from a month ago. The only other way of watching old EastEnders episodes is buying physical videos of them; I know some users on this wiki own these and may be able to upload some onto sites for you. I know the video sharing site Dailymotion has a lot of old and recent episodes; try searching a date or episode number on there.
It would be very difficult to collect every single episode and watch them. It may be easier to just read over this wiki and Wikipedia if you want to find out backstory. Soaps are made in a way that you can start watching at any time and very soon it'll feel like you've been watching since the beginning, as storylines go by on a regular cycle.
There's a channel called Drama where they are currently showing all the old episodes from the 80's. You can catch up on on UKTV Play. I'm not sure if you're able access any of this from Australia though.