Why is this so hard

So I’ve been self teaching myself for months now. JavaScript. I understand syntax, how loops work, OOP, dom manipulation. But I just can’t put 2 and 2 together. I’m not crazy smart, but I’m not like dumb either. Academically I’d say I’m maybe just a tad above average… But man! Even 8 difficulty on code wars stumps me sometimes. I’ll admit I did rush through html and css. Idk if this burdened me but ahh. I feel so stupid and defeated. Does anyone have advice ? I’m pretty much done with FCC JavaScript. Should I do the Odin project from the start etc?

Thanks heaps in advanced