What are you trying to accomplish? When you look towards others who have done it, you’ll see that some of them had all the advantages that you don’t. Pay them no attention.
Seek out the ones who have done it with a lot less going for them than you have- less money, less talent, less experience, fewer connections. Look for the ones who were in the wrong place at the wrong time, yet still managed to get it done.
Next time doubt creeps in, instead of making excuses and asking “why me?” try asking “why not me?”