its necessary to bulk to gain any significant muscle. you are either gaining muscle or losing weight (bulking/cutting). If you want definition in your chest or physique than you're going to want to...
I'd say about 12-14%. You're still young and you're still growing. Keep trying to get bigger and as you grow you'll eventually reach your goal. Keep up the work!
If you're eating enough you shouldn't lose any strength. If there is any strength lost it shoulnd't be a lot. If it is a lot then it's all in your head
Try eating the majority of your carbs before the workout. I've been doing this for the past month of my cut and all my lifts have significantly increased ! aim to consume your preworkout meals around...
Sleep more, eat more. Simple as that
Time your pre workout meal about an hour or so before you workout. However everyone is different and the time period before your workout might be different
And...