Upgrading pedals and wheels on 04 Trek 1000

Hi , I just recently got into road biking and enjoy it so im thinking about a few upgrades such as the pedals and wheels, any ideas.
There are plenty of pedals on ebay that go for great prices but i dont know if certain pedals fit on this bike or are all pedals universal?
also same question for wheels , can i buy any wheel?

What sort of pedals are you currently riding? Do you have road or mountain bike shoes that accept pedal cleats already?

IIRC, you're riding a fairly recent road bike as in the last thirty years with conventional cranks. Any modern clipless road pedals will work for you. There are cruiser bikes and department store specials that take a different pedal threading, but I'm certain this doesn't apply to your bike based on your recent thread on shifting.

FWIW, if you're not already I'd strongly suggest cycling specific shoes matched to clipless pedals. The type of shoe and pedal depends on the type of riding you expect to do and whether things like walking comfortably around cafe's is important (think recessed cleats). I hope you already have some cycling shorts to cut down on chafing and to make longer rides more comfortable and cycling jerseys with rear pockets are key for carrying food and things like rain jackets and spare cash for longer rides. I'd put money into those things before chasing bling wheels.

Good luck,
-Dave