League of Legends (LoL) Question: How to don't die like this with Annie? And why am I so noob?

Molten Shield only costs 20 mana, so feel free to spam it in order to gain stacks of Pyromania if you need your stun to be safe. Disintegrate also has a significantly reduced cooldown when you last-hit minions with it, so you can charge up your stun by farming as well.

If you know your limits, you should have very minimal time where you're vulnerable and can't charge your stun up in time if the enemy engages on you.

What you should do against this fed champion when you are behind or if he can kill you in one shot:
1) put yourself in a good position, stay near tower so it will be harder to go against you or to deny stealth.
2) you should have wards and vision around you so you will have enough time to leave your lane and go to safer place with team mates.
3) buy the right items, this kind of skill is mostly on experience and trying new items and know most of the items there are in LOL, Zonya for example can counter most burst like Syndra or Zed ult, and give you armor against lethality items and there are much more. You should always buy items after looking what each of the other 9 players bought, it will let you know what you need to defend from and what king of aggression you can put into the game.
4) specific from Annie, you should play safer if you don't have the stun ready, and after you have it ready do not waste it on minions and save it for the right time. (if you try to clear the wave and there is no risk you can use it on minions...)




This is a more general message I just wrote to other question:
League of legends is hard game especially in the start, there is so much you need to know to be good in the game

1) first of all know champions, what are they doing, what they can do, what they can't do. All of the champions, yours, your allies and the enemies.
2) you need to be skilled with the champion you are playing, it mean to learn what to buy, what combos do he have and be able to do the things you want to do in the correct time.
3) you need to learn the macro playing: laning (CSing),to go for objectives (towers, inhibs, dragon, baron, sometime even red and blue buff) , when to split, when to group, and so on

This are the main things you need to learn to be a good player,

You can do it by practice, read guilds, watch other players games, watch so streamers and youtubers and so on.

If you have any specific question will be easier to answer