On the left, there are filtering boxes, where you can select the type "Free Webinars", available for everyone; or "Premium Webinars", which are available only for those who had acquired a PMI Membership. Saving Changes...
I have been using LinkedIn learning, projectmanagement.com webinars and events organised by my local PMI chapter.
I really like LinkedIn learning for new topics and there are videos from about 15 minutes (0.25 PDUs) to hours.
As discussed by others, webinars are great and have some really good content. However, it's slow to earn PDUs as you are earning 1 at a time with these methods.