help writing song

hiii, ive been really struggling musically lately, ive been really wanting to make music like "No Below" By Speedy Ortiz, and honestly don't know where to start.
I'm pretty alright with settling on chords and putting lyrics over it, but once it comes to creating a melody or adding literally ANY other instrument it kind of falls apart. 

My past songs have been mostly acoustic guitars with just repeating chord patterns, but i have an electric and bass guitar, so im not a stranger to either instruments.