Do taxes and charity fundamentally come from the same source?

The WPA and the CCC created a lot of meaningful jobs during the Depression. Government funding for infrastructure can create good jobs.

Taxes and charity do not come from the same source. Why would you think that?

There is some overlap between charity donations and taxes, but there are a lot of areas that are separate. Try finding a charity that would provide you with disability for schizophrenia.

The government is not interested in creating jobs that are desirable for the recipients. It is interested in providing income for jobs that are in the national interest. If you are happy to sit back and live off your disability payments then the government has done its job. It does not need to provide you with work that you would consider meaningful, though you are certainly free to look for such work on your own, and the government will even continue to provide you with a portion of your disability if you find such work.

As to what a desirable job is, that will vary with the individual. We can’t make the decision for you. To one degree or another the salary that you get from it will be a factor. If you can’t think of a desirable job then stay as you are.

No. Taxes are involuntary and assessed by the government for operations of the government.

Charity is voluntary and most often not for governmental operations (although that can happen if the government fails to do its job)

They’re fundamentally from the same source in the sense that they require money, and money fundamentally comes from the central bank.

“If one is short then the other takes over.”

Charity does not somehow fill in for shortfalls for spending on public services. At least to not any remotely adequate level.

“Also can the government help or create desirable jobs for those in a rough patch?”

It can do. It already hires people to work in public service jobs. There are some who propose a Job Guarantee system to maintain full employment.

“What would you consider a desirable job?”

An astronaut.