Hi Rahul, Vladimir
We're not providing a general access sandbox site for Totara 13 as with the addition of Totara Engage and Totara Perform, alongside all the updates to Totara Learn, the TXP is a powerful piece of software which is best represented through a guided tour by one of our Alliance Partners.
You can also sign up for the next TXP demo webinar and we have a range of webinars
on demand that walk you through some of the new products and features available across the Totara TXP.
Having said that, right here in the Community we're using Totara Learn 13 and (as of today) Totara Engage so you can get a feel for some of the new features and functionality available now.
Cheers,
Meredith