Here are a couple of tips for mixing:
1) It's a good idea to use some compression on your mix bus/master. The way you have it now, the overall volume of the mix increases a lot whenever you have the vocals playing, and when the vocals go silent, the overall volume decreases a lot again, and this has two effects: it makes it feel like the vocal was just pasted on top of the music rather than being a part of it, and whenever there's an instrumental part in the song, the whole energy and the momentum immediately disappears. A bit of compression on the mix bus or master would make the vocals feel more like they're a part of the music, as well as maintain the energy better during the instrumental parts.
2) The vocal sounds a bit boxy and muffled right now. You could use EQ to cut some frequencies around 700-1k Hz and boost the highs to make it sound more balanced. It's especially a good idea to reference some professionally produced synth pop tracks while mixing to get your ears used to the kind of vocal sound that people expect to hear in this genre of music.
3) Be careful not to mask the snare drum with your vocals during the chorus. The vocals are obviously a very important element in the mix, but the snare is usually even more important. You could try ducking the vocals by a few dB for a super short amount of time every time the snare hits, like what you would normally achieve with sidechain compression, but in this case it's probably easiest to achieve it by drawing in the volume automation manually since I assume you only have access to a pre-mixed instrumental track. If it's hard to get the snare to cut through your vocals otherwise, you could even consider adding in your own snare sample and layering it with the original snare to get more control over the sound (and if you do do that, then you can also use that snare track for sidechain compression, which is nice).
Also, it sounds like your vocals get a little bit ahead of the instrumental track starting at 2:32.
Other than that, it sounds pretty nice.
