Next steps after claims filed

I went and files claims tonight of all the things like ptsd, high blood pressure, anxiety and depression and couple of more for knees and feet. I answered all the questions on va.gov and submitted as I have more things to upload later. It said I have one year to do so. My question is that I was not formally diagnosed with most of things on my claims by medical professionals so i dont have many things to upload other than couple of private medical records that i went to see doctors for. I wanted to apply sooner than later for back pay and in hopes of getting some help from VA about what my next steps would be. Would the VA send me to the doctors to get diagnosed when they review my files or would they just simply deny my claims for lack of evidence? do I need to take it upon myself to seek diagnosis from private doctors within one year? I do not have much money to spend in private doctors and tests so I wasnt sure what I need to do.