how much would health insurance be for a person with no family and no health issues?

A different amount in every place. It could be 200 or 1000 or 50 or any other number, depending on where the person lives, which health insurance the person picks, how old the person is, and many other things, but the most important is where the person lives.

Age would be the first factor here...along with location. States have varying rates...heck, even counties have varying rates...

Varies a lot depending on the coverage, deductibles and copays.

Depends on the coverage and deductible you want. Also varies by company and state.

Health issues aren't used against someone at this time. The cost depends on your age, income & your zip code & what plan you choose.

Very roughly: monthly cost of $10 times your age.

Depends mostly on your age but also your zip code and very much on your deductible. Most people buy via their work which might be discounted or even free. Full price for a healthy 56 year old is about $700 a month for a policy that pays for a flu shot, but nothing else unless I spend over $7200 in a year. Because my income is low, I get subsidies. I went without health insurance for most of my adult life and never needed it.

It could depend on his age to start

a whole damn lot. Apply for government medical insurance and it "should" be more affordable than out of pocket expenses .

Likely depends on what kind of treatment they will want during for their health insurance

There would be many different prices from different health insurance businesses as well.