im 18 and ive been training for almost 2.5 years but I still have problems with my chest. When i started my chest was one of my smallest and worst body part. now its way bigger but not aesthetic at all. Basically, I cannot seem to get that line that divides the pectoral muscles so looks like i have tits instead of pec(when im shirtless.)

im sure this has been debated countless times but can you add mass to the inner chest? ive asked some people and some say yes while others say no. I was told to just get my chest as big as possible which is what ive been trying to do lol.