UI for multiple forms with several input fields needs to be designed? How do to make user not get lost filling the form?

I have long and multiple page forms. I have made them into sections by using accordions so that user has ease of identifying the sections and not get lost. Is there any way to make the journey for user interesting since the form is long enough(takes upto an hour to fill entirely)?

Providing reference links for UI is much appreciated.

Thanks in advance