An idea for a wizard character

Okay so, this post may seem stupid but I wonder what fellow DnD players think about this HAHA
I'm not in a campaign yet cuz Im pretty busy studying these days but I do want to play DnD a lot. I was just thinking about a character so I have something ready when I do actually play. Lmk your opinions and whether you would let this on your table or not!!

I'm super new to this, excuse my ignorance please LMAO

Okay time for the idea

-Character backstory begins-

(Since this is a freshly new idea and not a fully fleshed out character, let's just call this fella Henry.)

Ever since Henry was just a little boy he had dreamed of being the greatest wizard of all time. He spent his days slouching over books, taking lecture after lecture, from one academy to another, studying until every one of his hairs became grey and his beard reached the floor. He worked as a lecturer, did some mischief here and there, entered dark forests and caves in the pursuit of knowledge and...he really *did* seem like the greatest wizard of all time. I mean, ask his students, the people that rarely got a glimpse of him. What couldn't he do? Why push it further? Henry just *knew* he was missing something. He could be even *better!*

Well, all those years neglecting his physical health took a toll on him. His eyes were barely working, all those explosive spells clearly didn't help his ears. That posture? No better than a shrimp. How could he chase knowledge if his knees gave out after 4 steps? Whilst dwelling on his situation, at the back of his mind he remembers something...Shouldn't there be a potion for this?

Recalling the tale of a potion that grants eternal health, he decides to look for it. Nobody really knows whether it's real or just a rumor. C'mon, a potion that cures all your discomforts? That's gonna cost a lot of Clerics their jobs. But hey what do you know, after overcoming dozens of obstacles he finds it! Those obstacles gave him quite the ache though...so he chugs down the entire bottle and...He feels like he's 20 again! Even though he may not look like it his eyes are as sharp as an eagle's, his ears can hear grass grow (of course, not literally). To celebrate, he casts some fireworks! But instead of fireworks, acid comes out. Alright, just a little confusion. A small flame could do. Instead of a small cutesy flame, you'd think he cast the power of the sun. After a couple of trials and errors he realizes that he can't control the magic he casts. It's like they have a mind of its own! Nothing works the way its *supposed* to work!

Turns out that you have to take the potion in really small quantities since its ingredients *really* mess with your chemicals. Since wizards have to backtrack to cast spells you kinda need your brain to work properly. When he does think of a spell, the train of thought goes off rails. Like, *really* off. Say, he wants to use telekinesis. There's a small chance that it will go the way he wants but also a large chance of him accidentally raining a thousand meteors on his house. He's in trouble? Well, just use poison spray! Nope. You just sprayed yourself. Okay, you can't go wrong with fly. Congrats! The enemy gains a flying speed of 4 feet. What a devastating attack.

Figuring he can't trust on his own spells anymore he decides to accept other people's company. Maybe he can find a cure for this nonsense.

-Character backstory ends-

I know some spells don't match with certain subgroups but cut me some slack haha! So basically, as he levels up he won't really *learn* anything new, his spells will just...stabilize. Anyway, what do you think? What would you change about this?