Is there a position available anywhere in the world where I can simply take an assessment to identify my skills and capabilities

I've never seen a job do this in my entire life. Usually when you do see a job that offers this, they're doing it just to make sure you're intelligent enough to read so you can work in a stockroom or do call-center work. The military kind of works this way, but I have a feeling that's not what you're looking for.

am seeking a different type of work that doesn’t require returning to school, interaction with others, or leaving my home.

ngl, after many years in the corporate world, this is going to be very challenging to find, after the covid remote-work trend cooled down, these jobs became highly sought after and there is competition for this work.

I don't mean to be too discouraging here, I just know how rough it is and the reality of trying to work with neurodivergence that makes certain kinds of work really unpleasant and the false promises of the corporate world. You may have to practice some level of radical adaptation to less-than-ideal conditions. Before that though, look for work in logistics, data analysis and auditing, they often have outsourced teams that do pretty quiet, tedious work from home and usually provide training since it's their own company and custom software.

You could consider getting certified for things that don't require schooling, tech certs and things like Salesforce specialization allow for a lot of personal freedom, but you will still have to talk to people a lot to get work and design systems to spec. A lot of these jobs might have limited futures though with AI.

In the end, getting the job you want is like getting a loan for a car or something. Just like you have to prove to your lender that you don't need the loan, you have to prove to your hiring manager that you are in fact social and comfortable in any environment, the very last thing most managers of small remote teams want to deal with is the worry about someone with a health condition who may be unreliable.

Mask up, make calls, pad your resume out the wazoo and start dropping applications everywhere you can. Be aware there are a lot of scams going on where they offer you insane wages for working a few days from home and other too-good-to-be-true offers that are designed to suck in neurodivergent people, be very careful and if anyone, no matter how real and professional they seem, asks you to put up your own money for anything to start, drop everything and run.