Honestly, this is a really important decision and you shouldn't rush just because your parents are pushing you. I went into my profession pretty young, jumped into something new right after school, and I got lucky - found my calling. But I see that it doesn't work out for a lot of people. A gap year can help you figure out what you actually want instead of just coasting on momentum. The thing is, how are you planning to spend that year? Just working a checkout job and saving money is one thing, but working in a field that interests you or is close to a potential specialty is something else entirely. You get to see from the inside what it's actually like, and maybe you'll change your mind, or conversely, you'll realize you need that specialization.
On the other hand, after taking a year off it's sometimes harder to get back into study mode. Your classmates will move on, and you'll be a year behind, and that can feel awkward. Plus government-funded spots are allocated every year, so if you don't get in this year, competition could be tougher next year. Maybe a compromise would be to enroll but pick a program that lets you work at the same time? Or even defer just one semester while your parents calm down and realize you're not against education, you just want to figure yourself out first?
The main thing is - what specifically scares you about studying? What do you mean by psychological unreadiness?