Offer them different things frequently, and show them you enjoy them they soon follow suit

Do it subtly. E.g. if your trying a new flavour sauce in a meal, separate theirs and only add a small amount of the sauce so that it’s not overbearing.
Also I tell my kids that they have to try it but they don’t have to like it. That usually gets them to take a bite of something new. There is also the ago old, keep offering it to them as it usually takes around 10 attempts before your taste buds get used to a taste.

My son is the same. I just ask him to try one bite and then leave it if he doesn’t like it.

We used to ask our daughter to try a little bit. If she really didn’t like it, she could stop eating it. But not before trying. That was the rule.

Something else that helped us with lunchboxes was bento style boxes. I’ve used cutters to make sandwiches more interesting. The dividers mean foods don’t touch, so she’s happier. You can get colourful foodpicks to stick in fruits/veg/cold meats/cheese. There’s also food safe markers you can decorate foods with. I try to do “safe foods” and add in something different to try, with mixed success.

This is my life basically. We’re at the point of seeing an OT for help for my child’s sensory issues. At a workshop I attended recently, the OT stressed that ANY interaction with new foods is good and it’s important not to make it a stressful situation for either of you. If you child wants to just touch it, or smell it, or play with it, that’s fine. That’s a start. You can ask if they might just lick it, or give it a little kiss. It sounds silly, but any interaction is a positive and increases the chance the food might be nibbled next time.

Maybe make one day of the week “try new thing” day. Look at the recipes and choose together,get them involve in cooking.