First playthrough and afraid that I might miss something
Thank you all! Here is a list of all the tips I received to help others like me in the future.
Thank you all for the tips, you have been very helpful! Reading your comments made me understand that to not miss something, or someone, in one playthrough, I would have to use a guide. So I've decided that I'll use all those good tips that you've given me so far (as far as I understand they will help me to not miss/skip a bigger part of the game) and other than that I'll go in blind. Using a guide would spoil the game and obsessing over obtaining every single item in one run would take away a bit of the joy of experiencing the game for the first time.
If someone in the future is afraid that they will miss something when starting to play this game, I will here list the tips that I received in a, kind of, spoiler free way (I hope everyones ok with me copying their tips, otherwise let me know). May it help you like it will probably help me!
Remember that I have not played the game so the information may not be correct. If you have played the game and notice that something here is wrong, tell me and I'll edit the list. Here we go:
General tips
Check Shrine Portraits: Look at the fast-travel list at any shrine; if you see a character portrait next to a location name, it means an NPC has new dialogue or an active update waiting for you.
Talk to everybody. Exhaust all dialogue.
If you see an old guy in white robes, talk to him immediately. He’s one of the few NPCs who disappears when you walk too far away.
If there’s a small old dude in grey robes, talk to him, but be warned that he generally advances the story. Read his dialogue options carefully because there is a point of no return many people trigger with him. (The storyteller?)
There is some kind of a storyteller character that might advance the story when speaking to him, so be sure to have completed what you want to do before doing so.
Selling your essence flowers instead of redeeming them every time you want to level up. Selling your essence is a much quicker process than trying to break it down inside your menu. (I have no idea yet what this means)
Don’t give your chisels away.
There will be 3 doors with riddles on them, I suggest looking up the answers. The wrong (or right) answer can either teleport you (makes it harder to track your progress because you don’t know where you are) or potentially lock you out of content.
Before finishing the game, make sure you have collected all the Stone Needles as you will be getting upgraded versions of them in your next playthrough. If you have missed any Stone Needles, your NG+ playthrough will only give the base forms of the ones you have missed and you will need to do another NG+ to get their enhanced versions.
Act 1 (Worships)
After defeating the Act 1 boss you get the chance to talk to the storyteller character. Don't decide to "continue forward" if you have stuff left to do or places to explore in Act 1. Maybe a cave that you haven't explored beside the storyteller?
Act 2 (Cloudspire)
After the first shrine found in act 2 you may find a cave. Do not enter this cave because it leads you directly to Act 3 (Zhenwu) and will break questlines. If you are stupid (like me), forget this, and go through the cave anyway, use the first shrine you see at the other side of the cave to go back to Cloudspire. This will not destroy your playthrough and your questlines will be safe. Proceed further than the first shrine and you may have messed up. I dont know, I haven't played the game.
During this act you will get to a palace. This palace will have a basement with an elevator (rose petals leads the way to the basement). Do not go down the basement before exploring the rest of the palace first. If you go to the basement first it will block some dialogue for a questline.
Act 3 (Zhenwu)
Do not talk to the storyteller (if you see this character in the end of the act) before making sure that you've finished exploring and have completed the quests.
Thank you once again for all the tips!