The question I hear most often from new writers is what the heck am I going to put on a website; I haven't published anything.
If you're just starting to query, or querying again after unsatisfactory results, think of your website as the director's cut of your query.
Your query must be very short; 250 words is the sweet spot.
That means you had to leave out a lot.
Start with your bio.
You can put pictures on your website. Pictures of your dog/cat/dragon.
Even though I love looking at pictures of babies, I do NOT suggest you post pictures of your kids online.
You can elaborate on hobbies you have, or where you live.
I've had intriguing conversations with writers about all sorts of things that I read in their bio.
You can talk about your writing if you want. You can post a (SHORT) excerpt from your book.
You can talk about things you value, or good causes you're involved with.
I do that on my own website.
And you can have a place for people to sign up for your mailing list. A robust mailing list is the #1 thing I look for when I've found a book I like, and an author that sounds conducive to work with.
Get a URL that's as close to your name (or your pen name) as you can.
Wacky URLs like FlitteryGibbertyBoo tell me you're not taking this whole thing seriously.
URLs that are hard to spell (mur3skeyWr9 for example) are contraindicated.
If your URL looks like a password, time for a new one.
An effective author website can be a big help for your stalwart little query.
Lack of one isn't a deal breaker, but why not use all the tools you have at your disposal.