yes, guides are absolutely not needed to reach end game or 'have fun'

read the skill tags on the gem you want to use
search those tags on the tree
also learn what some hidden tags would be - eg lightning damage is also elemental damage, so both those type affect it.
they are all generally in the same area, so you might be refunding 5 nodes here and there to try a different node cluster instead.. but that is how this all works.

those are the nodes that will affect your skills. workout which ones you want, whether its the damage, speed, duractions, etc depending on how you want to play it, and path there

also defences require more then 1 layer. to not end up back here in a few days complaining about 1 shots like everyone else. you need to focus all your gear and passives into 1 type of defence, but also other defences that synergise with it.

If you think like a elemental sorc as an example: I want to do cold or lightning damage? Spec those stats in passive + spell dmg/lightning dmg mods on gear. Obviously mana, mana regen, hp, and resistances are also important but those are fundamentals. If you like a spell, USE IT. Same for phys damage, think of spell dmg but just physical tag instead. Read and make sure tags of what skills you use match wording in the support gems or your gear mod traits. And also support gems add some that make it fun first then worry about damage after you enjoy using it. I think early on as a sorc I just used whatever was fun for me at the time. When you die...learn what caused it? Sitting in one spot too long, probably had a aoe of poison or corrupted blood on the ground you were standing in, etc.

Edit: poison debuffs/bleed etc You get a charm slot when you get a belt, make sure if boss is giving you pains to check your resistances and what charm you are wearing. They make a night and day difference when you gear for the right circumstances.

Your name though 🤣