One single thing that help your survive and keep going is to think, and act like a child
As kids we all are just curious about everything, every single thing brings us joy. There is nothing to worry about in grad school if you're curious about learning everything you don't understand or otherwise unfamiliar. The fact that you have started grad school means you survived so many assignments, exams, lab experiments, writing reports, took a significant amount of courses, and what not. You got this, and you can kill it- but never give up on that one thing- curiosity. Come on bro, Humans figured out rocket science, without digital computers!. With the amount resources we are blessed with today, we can do good and big things.