Help new Templar

I guess I have a lot of questions, first off I'm very new to this game (also i'm playing on xbox i don't know if that makes a difference)

So I picked Templar to play. First question is what does Guardian, Hierophant , and Inquisitor mean?

I guess my 2nd question is whats the best weapons to use for this character

I'm here to learn so please any advice is good advice at this point suggestions are much appreciated

First off, Welcome to the Path of Exile community! There's definitely nothing wrong with asking questions, so don't hesitate to ask for help with things that don't make sense to you yet. Many of us have been playing for years, so don't feel like you need to learn everything all at once.

As for your questions, let me break those down broadly and then define it a bit tighter for you.

Guardian, Hierophant, and Inquisitor are Ascendancies. Each base starting class (duelist, witch, ranger etc.) can complete the Lord's Labyrinth (Located at the bast of the statue in act 3, then through the waypoint system at any time after that). Completing the Labyrinth allows players to choose one of the ascendancy sub classes available to them, which have different bonus properties that specialize characters towards different strengths. I highly recommend looking over This Page to explore these in further detail.

The TL;DR is that each character you make should have a rudimentary 'plan' that you intend to follow, and you pick your ascendancy based on what will optimize that build the best. So, thinking about that, on to your question #2.

The best weapon to use depends entirely on what it is you plan your character to do. There are so many choices and unique items that all have different interactions with the skill gems in the game and the sub classes that you should hopefully have an idea before you commit too many 'permanent' decisions, only to change your mind later.

All skill points that you invest in a character tree can be refunded by using 'orbs of regret' or the respec point quests in game (in limited number). But since Path of Exile uses these orbs as one of it's forms of currency, it is advisable to plan ahead to save money in the long run. Respeccing can be expensive, and ascendancy classes especially so. That being said, you hopefully know if you want to play a ranged, melee, caster, or totem build (or one of many other hybrid things).

So our question to you is: What do you like to do? How do you want to play? What have you used so far, and what do you want to try out? Have you experienced many of the options and have choosen the one you wish to work on as your primary focus?

Wands/sceptres for spell casting are good, but sometimes spellcasters use bows or even daggers. Melee characters don't always use maces, swords, and axes... sometimes they are unarmed! And some people prefer to let totems and minions kill things for them.

So considering all of this, in order to give more advice we would need to know more about where your experience lies, and what you enjoy so far about Path.

The best advice I can give you at this point is not to treat your character as 'your only character', much of the game is about designing new builds and leveling new characters to try them out, finding what their strengths and weaknesses are, and then remaking or reiterating them in other forms to make the purest or 'best' version you can.

So don't get discouraged if your first attempt is less powerful than you desire, keep rerolling and learn more and more until you're really proud of what you've made. Set goals for yourself in terms of clearing content and damage, survival, money, etc. Many, many players don't even typically kill the end-game bosses with their build, even famous streamers typically don't play builds that can do 100% of the game content. Find a happy medium that aligns with your expectations and play from there.

*Edit*
I also highly recommend checking out the build guide listings to look over other player's creations. Following their thought process and designs can teach a lot of the game to newer players while keeping them from pitfalls or difficulties. Also, using a skill tree planner is really helpful, either the one on this website, the offline skill tree, or the ever popular 'path of building'.

Cheers