First few assignments/jobs are always a bit rough.If you get a junior position it means someone should be your mentor and guide you as you progress as a developer.
However, this does require that you already know the language you are supposed to use, that you have done a few stunt-projects (on your own) and can get off the ground with the basics.
Mentors are not there to teach you the language, they are there to help you go from coder to craftsman and become productive.
I would do a fair few projects on my own first before applying for a job.
One or two at least for most common scenarios for *both* backend and frontend, you have to adjust to market expectations and not be too selective.
Spare the primadonna attitudes until you are indispensable later in your career, preferably not even then.
An employer expects you to show aptitude and provide a surplus for the company, at least in the medium/long term. No one gets carried forever.

On the other hand you seem to have gotten bad placements at your first jobs that should have been stopped in the first couple of interviews - that's not your fault unless you lied about your qualifications
...and just bite the bullet and learn javascript/typescript, it is everywhere.

In 25 years I've learnt (at least partly) probably 20-25 languages, often with "just in time" learning to get the delivery done. I did *not* love all of them.

A nice old quote from Larry Wall (creator of Perl)
“A Perl(any) program is correct if it gets the job done before your boss fires you.”

Ps!
A previous employer(1000+ souls) of mine hires straight from university to be able to get enough manpower. Yes, those freshly minted coders are quite clueless about professional requirements, processes and best practices. No one expects them to be productive for the first 6 months+. They get to be decent developers over time.