If it was as easy as "knowing how to" someone would've already done it or at least attempted to.*
Plenty of people know how to, 10,000s of researchers, perhaps you know someone who does.
Did you know that your local veterinary shop has enough drugs to kill 100s of people?
Why doesn't it happen?
* It's not that easy.
* There's a ton of regulation that is hard to circumvent, on purpose.
* There's a gigantic deterrent called "spend the rest of your life behind bars" that people tend to avoid.
An LLM, even the most advanced one, does not make any material change in any of these. You cannot bullshit your way into "uhh, I need Ebola samples for ... reasons".
Unironically, your Sunday movie portraying a super-villain jeopardizing a city with his "home lab" full of flasks with colored liquids and BioHazard signs push way more people into becoming interested on this than having access to an LLM.
*: Okay, like 5 people, and way before LLMs were a thing. This has been a thing for decades, we're fine.