How can we disable membership auto renew on our website?

To cancel all future renewal you can do the following:

Go to Payments-Recurring Payments and for any future payment that you want to cancel you change the next billing date to a prior date (this way it will not bill it). You can also just set the end date to today's date. Either one will cancel the future payment.

Moving forward if you don't want your memberships to auto renew (meaning people who sign up), go to Products->Products->Subscriptions and remove the Renewal Product from each membership - blank out the description field and set the renewal price to 0 and the renewal subscription to 0.

Keep in mind without the auto renewal you will need to send out emails to members each month reminding them to renew. The system will have no way of doing this for you since you will be removing the renewal product.

Alternatively we could also setup a notification to send to members X number of days before renewal takes place, with a link on how to access their account to manage their membership.