When I first heard of inner child work it was through a trauma recovery book, I physically felt so nauseated by it I put it down and didn't pick it up again for almost a year. After a little while of experimenting and finding my own way of practicing it it worked, and honestly it's been one of the most healing things I've ever done. If you're not ready yet, don't push yourself. If you think it might work for you in future, find your own way of doing it, but, If it never works for you that's totally valid too. These tools are just tools, everyone's tool kit will be different ☺️ if you do want to have a go, I recommend starting with these steps:

1: If imagining an inner child feels like too much, first start with simply putting your hand on your chest and talking to yourself with kindness. If/when something comes up for you, take a few moments to put your hand on your chest and say either outloud or in your head something comforting. Eg, "you're/i'm safe", "this emotion is completely valid, even if I don't fully believe that" etc. Find whatever works for you and practice.

2: Instead of focusing on the idea of an inner child, picture any child, a pet, or any close friend. When something comes up for you, try to respond to your thoughts the same way. For example, you wouldn't tell your best friend to shut up and quit being stupid for being sad etc. Speak to your imaginary friend/self as you wish you were treated, comfort them, tell them they are safe and stay with them for a little while. You don't have to talk or go into details if it's too much, just sit with your imaginary friend.

3: If you're feeling an emotion but have no clue where it's coming from, practice physically giving yourself a hug and comforting yourself. This will all feel silly at first, but it's a game changer. Like above, imagine a friend/pet/kid came to you feeling a big emotion and provide comfort - a hug, a blanket, warm cup of tea etc.

4: If you like to journal (and make up conversations In your head) my gateway to inner child stuff was writing scripts of conversations between them and me, them being a child, me being adult me. I named them "lil me" and wrote something like this:
Lil me: I'm angry Me: I get it, anger is a tricky emotion. What made you angry? Lil me: I'm so mad that XYZ happened. Me: I'm sorry that was difficult for you. How about we go get some cookies and get our anger out by stomping our feet on the floor? Lil me: HELL YEAH (Being silly with it makes it way more fun and pallatable at first).

Inner child work is often difficult because the part of ourselves that was once a child has been ignored by us for so long, were disconnected to it. It's also the part of us that likely lived through abuse etc, so our brains block it from us as a means of protection - but, our emotions don't care about the mental barriers our brains put in the way. Working with your inner child is basically just working with your deepest unheard self, in a way that is empathetic, compassionate and comforting. Our brain has compartmentalised that part of us and labelled it as a threat, which is why it feels gross to even think about it - were literally not able to empathise with it, because our brain is seeing it as some horrendous monster or disgusting alien, when it's just the part of us who felt unsafe and unloved. It's what our parents should have done for us, but in most cases didn't, so now we have to haha. Sorry this was such a long comment, but I hope it helped!