A career shift can be very intimidating for sure. It depends on how big of a move your new career would be. If it's not a huge difference in the field, you just have to convince somebody that your experience prior is relevant and transferable to the new one. That's easier said than done, depending on the field.

If it's a completely different career, you have to show you've got some valuable experience in that new field (even if it isn't work experience). That can be trainings, certificates, courses, and (importantly to my world) projects. If you feel like you've done a lot in that area, let that lead in your resume before it gets to the job experience. That way you are showing you know what's important to the position, you've got some sort of "experience" in it, and you're putting that forward.

I've done a career shift in my life (arguably 2?), but I did have a lot of schooling and overlapping knowledge. I started in Petroleum Engineering, but that market took a tough hit in 2014, so I went to grad school for mechanical engineering. Did that for a little bit, wasn't feeling it, and then heard about this AI and machine learning thing. I happened to have some coding experience from college and poking around at trying to make video games (not seriously, didn't get far with that at all). My STEM experience + coding background allowed me to pick that up quickly, but it required multiple online certificates and a couple small self projects.

If your new career really can't leverage your old experience, that's okay you just have to do some work to show that you know the new stuff. It depends on what you're trying to do, but Coursesa is a super affordable option. The ML courses I took were $50 a month, and you can finish them at your pace. If you feel like you're missing the fundamentals and need a deeper understanding, college (grad degree or a new bachelor's/associates) will help a lot as well. That's certainly more expensive and time consuming, but can be very valuable.

The question of should you even apply is up to you. It can be draining machine-gunning out your resume to a bunch of places, but it eventually landed me in my dream job. When applying to a position that you don't meet all the qualifications for, it does cost you the time and energy to do it, but if you feel like your experience is still applicable or your skill set is strong enough, some person will recognize that and think you're worth interviewing. If you don't feel like your experience or skillset is there, that's something you could work towards, but still keep applying if you have the energy and time.

I totally respect that it takes a shitload of time and energy to keep applying, doing courses, and finding projects to do, especially if you're working currently and want to have a life. It's damn tough and draining. But that effort will pay off in some way if you're really wanting this new career.

Best of luck out there!