Is it a misuse of school resources to use school accounts for non-school work?
In the US and some other places there will be laws (at the State level) and regulations about use of resources in general, but for the things you suggest there should be no issues.
But this is because the libraries, in particular, at universities serve as a general public resource of information. You could probably get the same services even if not enrolled just by asking for assistance.
There might be exceptions, but for most universities the mission is varied and broad. A university is more than just a place where students are taught and more than just a place where research is done.
As long as nothing you do actually interferes with any of the missions (and sometimes even if you do), the resources are open to you and, it is citizen taxes that support much of it in any case.
Feel free.

The cases where you might run afoul of regulations would more likely be in the use of specific equipment purchased for one thing but used for something else.