However, i cannot stress enough that knowing theory will not help you magically make more complex progressions.
Exactly. And, I'm going to start sounding like a broken record on this forum, but music theory and composition are two related, but different, things. Plenty of people compose really excellent music with little theory knowledge, and many others have excellent grasps on theory, but have trouble composing. The analogy that some of my profs used back in the day was to think of theory as learning the language, and composition as writing a novel or book of poetry.
As for the OP, the request seems to be that he wants more complexity because he feels that it will be better. It's a bit hard to address the question without some more information or examples demonstrating where you're at in terms of simplicity/complexity. But, I will say that, in most forms of pop music, complex chord progressions aren't usually the norm. The chord progressions are generally quite simple and you'll find by close listening and learning that there are countless songs using the same few basic progressions.
As far as how chord progressions work, there are volumes of books written about this, so you won't get the answers you're looking for in one thread. But, some of the fundamental things you'd be taught in a first-year composition course (and find in countless popular music songs) are to move up in seconds or fourths, or move down in thirds or fifths (same as moving up in fourths) when stringing chords together. These are NOT rules, just tried and true approaches that work, and are good starting points. Common examples:
I - IV - V7 - I (e.g., Cmaj - Fmaj - Gmaj7 - Cmaj): i.e., move from the major tonic (I) chord up a fourth to the IV (subdominant) chord, then up a second to the V7 dominant chord, and down a fifth (or, up a fourth) back to the tonic (I chord).
I - ii - V7 - I (e.g., Cmaj - Dmin - Gmaj7 - Cmaj): i.e., tonic (I) chord up a second to the ii chord, then up a fourth to the V7 dominant chord, and down a fifth back to the tonic (I chord).
i - VI - iv - V7 (e.g., Cmin - Abmaj - Fmin - G7): i.e., minor tonic (i) chord down a third to the VI chord, down another third to the iv chord, up a second to the V7 dominant chord, and down a fifth back to the tonic (i) chord.
Another common example that does not adhere to the guidelines (i.e., not rules) above is to move down in seconds (e.g., i - VII - VI in minor keys). You won't find that progression very often in classical forms of music, but it's common in modern music.
A few other things to read up on are extensions (e.g., adding 6th, 7th, 9th, 11th, 13th, etc intervals to a triad) or even compound chords (i.e., playing one triad on top of another - similar to extensions) to add more complexity and richness to your chords. Also, consider and read up on the role of dissonance/consonance in chords and how they function to create tension and release in chord progressions.
Inversions are a great way to vary a common chord progression and are related to voice leading, which is also worth your time to get familiar with.
Hopefully, that's somewhat helpful. But, as Lydian mentioned, having examples to work from would probably get you more pointed answers and advice.
