Not seeing much progress

So basically I am just a newbie teen (18M) who's trying to build some muscle. My bodytype is skinny fat ( based on some internet pics of similar looking people it's between 20-25% bodyfat,I am not sure tho). I am 173cm tall (short Ik) and weigh 60kg.

Basically what I have been doing is push ups, bicep curls and wrist curls(using weighted backpacks), all of them are like 12 reps each and 2sets a day. I am also doing some core involving exercises like planks(30secs 2 sets) and situps (12reps 2sets). I mostly try to do all of them to failure each set.

Now, I have been doing these for almost a month, but I legit see almost no gains at all, like very little gains(my strength has slightly increased tho). My arms appear slightly bigger only after the workout but become same as it was before once the pump wears out.

So am I doing anything wrong? Or do I need to increase the volume of exercises to see faster results?