From what I've heard, the most secure way is to build your own from components that you purchase off the shelf locally.
Apparently, any computer purchased online can be secretly diverted for special treatment during shipping, before it reaches the customer.
But also know that every Intel CPU made in the last 10 years has a built-in backdoor. I assume this is also true for AMD CPUs.
I imagine one of the big breakthroughs soon in personal health will be:
some kind of way for people to analyze their own blood to understand their own health issues. Then anonymously use an online resource to find the herbal remedies, essential oils, appropriate foods, and other natural cures that will be most effective for that combination of issues.
It seems likely that the drug companies know this is possible and likely to happen, and have fought to keep it from the public and the doctors.
It does not make any sense that there wouldn't exist in nature a simple affordable solution to almost any kind of health issue that isn't life-ending.