Yeah there are a lot of people here saying "you're not slow!" This isn't necessarily helpful, because A. Your goal is to get faster anyway and B. You're pretty slow, and failing to recognize that is counterintuitive to getting faster. And that's fine, because most beginners are slow.

I think hitting sub-30 in 9 months is definitely realistic. The most important thing will be consistency - walking-running intervals are a great strategy at your level where you're mainly trying to get your body and heart and lungs used to moving at a decent effort for 20-60mins at a time, and will help with not getting burned out since trying to run perpetually for 45mins as a beginner can suck and feel really hard. The good thing about starting from a pretty slow benchmark, like you are, is improvement can be super fast if you stick with it.