The realms free trial isn't on my Minecraft. Don't forget that I didn't get the free trial...

I have just had a look at it shows you have to have a 10 user subscription to get a free trial.

We offer a free 30-day trial of Minecraft Realms to players who have not previously had a Realm and have signed up for a 10-user subscription.

Check it out on My Profile (minecraft.net) If you've got Minecraft Realms it shows up there

There is a free trial for Minecraft Realms when you first subscribed

If you were charged twice, contact Minecraft Support (not Microsoft Support) to get your refund

Hi DimmerMedusa11. To connect and play in the same world online in Minecraft: Windows 10 Edition, your kids will need to enter a Realm together. Realms, which you can read about the introduction to Windows 10

here, are a dedicated online world that lets players on Windows 10, as well as Pocket Edition and the Xbox One Edition invite their friends to play and create. Realms are available for a 30-day free trial, but after that it's a monthly subscription,
as the world is hosted on Mojang and Microsoft's servers rather than any of the individual players' devices.

To access Realms, launch Minecraft: Windows 10 Edition, click on Play. From there, if you see "30 Day Free Trial", click on it and it'll show the Realms info, as well as the cost after the trial period ends ($7.99/month). From there, go ahead and click
"New Realm" and set the world up as you would any Minecraft world. If you don't see "30 Day Free Trial" button in the list of playable worlds, click "Create New", select "New Realm" in the menu across the top. From there, you can either import an existing
world from either child's world list or create a new world entirely. Hope I helped answer your question!

If its not the above, then you need the Bedrock Realms Plus for the free trial.

What kind of subscription though? If it's a free trial, I could be wrong but I don't believe you get the free games with trials.