Hey man. Sorry for the slow response - had a really busy week.
I like the quirky synth at the beginning. I think it doesn't quite mesh very well with the chord pattern at :07, though, and the eerie synth pattern at :29 is also pretty dissonant with the rest of the instruments.
I'm also a bit confused that you tag the song as "happy." It doesn't really sound happy to me. When I think of happy songs, I think of a lot of major chords in a row and some more dynamic melodies. The texture here is really dissonant and creepy sounding, with a lot of stepwise movements in a narrow pitch range (for example, the chord progression at the 2-minute mark goes E-D-E-F#) and without a strong tonic (that is, a chord that the song is "rooted" in and keeps returning to consistently).
In short, I think you need to do the following:
1. Educate yourself on music theory a bit more. There are some great free resources online specifically for computer musicians, like this one: https://orchestralmusicschool.com/c/music-courses/music-theory-for-computer-musicians. If you're short on time, I think you would especially benefit from this lesson on chords: https://orchestralmusicschool.com/music-theory-for-computer-musicians-part-7/303
2. Listen to a song you really like, and then try reconstructing the chords underlying the music in FL Studio. Apply what you learned in the Orchestral Music School online lesson to understand why they sound good together. You can even try making a new song using those same chords in a new order or with a new melody. Just make sure that the notes in the melody correspond to the notes in the chords - that should help maintain the same feeling as the chord progression in the rest of your song, whether it's happy, sad, or whatever.
3. I'd also suggest spending more time on making a single song. It seems like you post a lot, but without a good idea of the intention behind your piece or the story you're trying to tell. Example: the author's description of this piece is literally "I had no clue what I was doing here lol." Contrast that with one of Waterflame's recent tracks: https://www.newgrounds.com/audio/listen/1198433. He and pftq are trying to emulate a style of piano-heavy techno music from the early days of Newgrounds. They likely spent a significant amount of time carefully selecting the instruments to use for the track in order to emulate that style, and the upbeat mood, rhythms, and chord progression are all reflective of that style too. Taking inspiration from other artists and specific genres of music is a good idea, for both you and Waterflame, but it takes a lot of effort and close analysis of what makes a song sound good to do that (see #2). It will become easier with practice, but right now I'm not convinced that you're making the sort of effort you need to in order to sound like Waterflame...yet.
Sorry if that sounds a little harsh, but to be fair, Waterflame didn't even sound like Waterflame in his first few years of composing. It's all a journey, but it's good to start early. :)
Anyway, feel free to hit me up again in a couple of weeks. I'll be out of school by then. Keep at it, Creeperforce24! ^_^