I just got Fuuka to join the team and I wanted to ask some quick questions before I continue playing, I really don't want to mess up again seeing as I had to start a new game due to my previous one having everyone severely under leveled. Orpheus is currently my main Persona that I use and because of this I have used a lot of stat boosting items, leveled her up a lot, and went to the arcade with her equipped. My question is, no spoilers please, am I doing the right thing? If I fuse her later on will I lose all these high stats she has?

You won't lose Orpheus's stats if you register her in the Compendium before fusing.  But I really don't think you're doing the right thing at all.  Why are you training the first Persona you start with?  It's okay to abandon her for good.  Fuse Persona into one that will match your level and train that one.  Unless you're playing on the difficulty lower than Normal, in which case I suppose it's not that big of a deal.

Stop;Orpheus is a terrible persona to be wasting boosting items and time on and she'll only lose her stats if you don't record her.
 
Edit:I'm guessing since you called Orpheus ''she'' you're playing P3P?

You need to get a stronger Persona.  He gets useless pretty quick.

You aren't doing the right thing.  You have a Pokemon mentality but Persona isn't really that.  Your starting Persona will not carry you through the game.  You need to start fusing new ones.  I know the first time (and the second and third and fourth etc. etc.) is scary, but it'll eventually become less so.

It's normally a good idea to start fusing new and better personas as soon as possible, since they don't level up as fast as the main character does. Although I beat the game with a LVL 42 persona :P

I don't think so; I believe the strength of the weapon you're holding affects the hit damage. Though maybe I'm wrong.
 
Anyway, the way to play Persona is to get social links (which give newly-fused Personas extra EXP) and try to fuse the highest level persona you can and utilize the social links. For example, if you're level 20 and you have a level 5 Emperor social link, then you'd ideally want to fuse a level 20 Emperor persona that has stats/abilities you want. Generally you want try to get every magic type in your array of personas (a persona with fire, another with ice, etc..), and go for the boosts when yo can (fire boost, ice boost gives +25% damage to that type of magic).
 
Once your persona has learned all its moves then you know that it's time to fuse it out. Just try to keep Personas that are close or around your MC's level, and you'll be fine.
 
Edit: Focus on social links or raising statistics; don't waste time at Persona stats on your first playthrough.

Consistent Conditions
-------------------------------
- MC Level: 47
- No other party members
- MC in "Good" Condition
- Enemy is always Withering Tiara
- Tartarus Floors: Block 4, Floors 136-138
- Weapon: Nameless Katana (ST: 168)
- No ST-boosting or AT-boosting equipment or skills used
- Minicrits and Full Crits don't count
- Damage while enemy is knocked down, enraged, distressed or shocked don't count

                        || TRIAL || DMG || AVG ||
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                        ||    1     ||  107 ||         ||
                        ||    2     ||  106 ||         ||
                        ||    3     ||  103 ||         ||
PERSONA #1     ||    4     ||  100 ||         ||
--------------      ||    5     ||   99  ||         ||
Saki Mitama      ||    6     ||   99  ||         ||
Level 39            ||    7     ||   99  ||         ||
ST stat 20         ||    8     ||   97  ||          ||
                        ||    9     ||   98  ||         ||
                        || AVG   ||-------> 100.9 ||
------------------------------------------------------
------------------------------------------------------
                        ||    1    ||  115 ||           ||
                        ||    2    ||  118 ||           ||
                        ||    3    ||  123 ||           ||
PERSONA #2     ||    4    ||  123 ||           ||
--------------      ||    5    ||  122 ||           ||
Vasuki              ||    6    ||  120 ||           ||
Level 38            ||    7    ||  121 ||          ||
ST stat 27         ||    8    ||  121 ||           ||
                       ||    9     || 123  ||          ||
                       ||  AVG   ||-------> 120.7 ||
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