I'm trying to understand, so kind of like the movie Casino and Mr. Rothstein. As long as you apply, you can work?
No. It's based on the needs of the mission versus the risk posed by granting that specific individual access to classified.
In my case, I have held a Top Secret/SCI clearance. Nothing new in my personal history would prevent me from being granted another top secret clearance.
If I applied for a civilian job (gov't or contractor/consultant) which required a TS clearance, the commander may grant an interim clearance based on the information I provided in the clearance application SF 86), and based on the fact I've held a clearance for 25 years previously.
If they don't really need me to access classified, I could easily take training courses or help with unclassified tasks while my clearance application is investigated. It's totally up to the commander.
When I first came to Hawaii, my company hired 2 more employees for my contract task. Neither of them had clearances. For the 6 months it took for their Secret clearances to be adjudicated and granted, I had to escort them into and around the facility. They couldn't work with classified, and if I left the facility, someone else had to be their escorts or they left with me. When I went to lunch, they went to lunch. It got old quick.
https://www.thebalance.com/sf-86-security-clearance-questionaire-4058541