It is my first time to V

[Raymott]

I don't know about these examples being serious enough writing but here you go:

1. Hello Folks, this is my first time to send a message to the Leeds support list. No

2. No, it'll be my first time to do anything quite like this. No

Both found here: [bnc] BNC Simple Search - Using the BNC

You may come with different examples while writing "first time to" in the search box as this search engine returns randomized results

No, I would consider neither of these convincing as 'serious' writing. Anything that has passed an editor (the human type, who weeds out bad writing) or two would do.