Many people don't know what else they need after buying an electric guitar for the first time, now let me give you some advice：
First of all, it is a good electric guitar cable to amp, because the general electric guitar comes with the wire is not very good, here Ebxya's electric guitar cable to amp is a good choice.
The second is to buy a protective bag, not particularly expensive but the protection must be good, attached: do not use the kind of waterproof bag sent in the general luthier.
Then you need to buy a set of string change with a small spindle and cutting pliers.
In addition, you need to buy several good plectrums, the thickness and shape of this plectrum depends on your personal playing habits, you can buy some back to try which is more smooth.
The above are some of the small tools and supplies, the latter will require some large budget.
Guitar-specific audio, the choice of this with your living conditions, if allowed, electronic tube audio is the optimal solution, but do not pursue it, think about your roommates and neighbors, I do not want to see your news in the newspaper the next day.
Another is the selector, it depends on your audio, if you are tube audio, then you can match a few almost single block effects to complement the silver; if you choose a digital audio, then in theory you do not need effects for the time being; if your living conditions only allow you to practice with headphones, then a comprehensive effect is enough.
I hope my suggestions can help you