friends how to stop overthinking my flaws and remain motivated?

i overthink too much about my flaws..even when i am studying i automatically start to think about my flaws and ruin my studies..i get depressed and anxious about future because of that..how will i overcome all this??i start to get demotivated and lose the will to function feeling its all pointless..my problem is i have very poor communication and interpersonal skills and i remain very anxious about how will i make it in this world..i have mental blocks when talking to girls..even in my class i dont have a courage to approach girls because i am boring and i dont have topics apart from studies..and i also feel that they will find me clingy..please help me how to unshackle my mind ..and will going to gym and personality classes help ???