📝My First Time (❌to) 🇬🇧
Here is a quick way for many people here

to immediately sound more natural, because this is one of the most common grammar problems on HelloTalk.
👎It's my first time to eat yellow tomatoes.
👍It's the first time I've eaten yellow tomatoes.
👎It was my first time to visit Suzhou.
👍It was the first time I'd visited Suzhou.
👎This is my first time to post on HelloTalk.
👍This is the first time I've posted on HelloTalk.
I call it a grammar 'problem,' rather than a grammar 'error'; you may hear the odd person or book which uses the infinitive form (to+verb) when talking about 'first time,' but it sounds terribly ugly. (So, please listen to me, not them, haha!😂)
I hope this is helpful.
Thank you, bye~😊
PS. This problem is particularly common on social media, when describing a photo.
*If you like my silly little English tips, please check out my others*