Need help to stop getting squished in maps

Hi everyone, like the title says, I could really use some advice as to how to stop getting exploded in maps. It's safe to assume I'm new, and my grasp on how this game works is tenuous at best. It took me about a week to get through the main story, and I'm only at the point when I'm doing tier 2 maps, but even in tier 1 maps I find that sometimes I just die, and I have no idea why.

Some links:
Me: https://poeplanner.com/b/tC
Build I'm Attempting to Follow: https://www.youtube.com/watch?v=ivYiKxYHyjg

My cold and lightning resists are both 75%, but my fire is currently only 73 (I'm going to fix that this afternoon). My chaos resist is sitting at -48%, but I do currently have Shakari, although without the Terror of the Infinite Drifts (not sure how to get that just yet). I have 1694 armour and 899 evasion, but the build I'm following uses Unwavering Stance, so I think that evasion is useless.

I just figured out how trading works 2 days ago, and the only thing I've bought so far is my weapon. I'm trying to work out what I need to stop occasionally going from full life to dead in a fraction of a second, even in tier 1 maps. I feel like it has to be some kind of chaos damage that is just destroying me, but doing some research, people say even hardcore players usually run around with -60% just fine. Do I just not have enough life? Is Unwavering Stance screwing me over? Maybe my armor rating is just super low?

I'm really at a loss right now, and honestly, even though I keep hearing that Zizaran has some of the best build guides, but I'm still too stupid to follow half of what he says in them. I feel like someone applying to an entry level job that requires 2-3 years of experience right now.

Any help/advice would be greatly appreciated.

Hey I'd focus on replacing all your gear with pieces that have life, the 2 uniques you're running especially. Chaos resistance is good as well, it's become more common over the years so it could be 1 shotting you, getting to at least 0% is a nice to have. Look into upgrading your flasks as well, you probably want an instant divine life flask with bleed removal and defensive utility flasks like a basalt, get freeze immunity somewhere on those and a unique lions roar flask for damage and defense.

I replaced my hands and belt like you suggested, and tweaked my resists a bit so I could put more health on stuff. Which ended up raising my health from barely above 3k to juuuuuust shy of 4k.

HOWEVER, one thing I I think I learned, that is not explained anywhere, because it's probably assumed knowledge... Leap Slamming isn't just a terrible movement ability, I need to do it to build up endurance charges. So Leap Slamming into fresh enemies is something that I always have to do.

BUT, more importantly. FLASKS!

The new me: https://poeplanner.com/b/Vc

I used Autohotkey to bind 1-5 to my 'G' button (because constantly pressing all the buttons seemed... odd), and suddenly stuff that was exploding me before almost seems completely trivial. I even managed to do my Merc trials, first try, with no difficulty at all!

So, my take-away is that, as I suspected... the issue is mostly that I don't understand how to play the game, and these guides never actually bother with that aspect, even though they're "beginner friendly".

using macros for flasks is a bannable offense