Call a Lazyblock as a Custom Field

Hi,

I really a newbie with this and I don’t really understand how it works but I need your help to see if I could do what I need with Lazyblocks :

I have several pages.
In each of these page I need to have a custom field where I fill in a simple URL
Each page needs its custom field with a different URL I fill in.
I need to call this URL from a plugin (WP Grid Builder by Themeone) that displays these pages in a grid. But each item of the grid need to link to the custom field URL I filled in on each page.

Do you understand the idea ?

Thing is these pages are Custom Post Type and I don’t know why but Custom Field are not displaying… I tried the classic way to enable it in Gutenberg but it didn’t work… Then I tried several php methods I found on internet to add custom field but nothing worked.

So I thought I could do it with Lazybloks.
So I created a block with a simple URL control and displayed it on my pages.

With the grid plugin I can call an “custom field” as URL but when I look for the Lazyblock I can’t find it. I just found this list of custom field names :

lazyblocks_icon
lazyblocks_slug
lazyblocks_category
lazyblocks_controls
lazyblocks_code_use_php
lazyblocks_supports_html
lazyblocks_supports_align
lazyblocks_supports_anchor
lazyblocks_code_show_preview
lazyblocks_supports_inserter
lazyblocks_supports_multiple
lazyblocks_code_frontend_html
lazyblocks_code_single_output
lazyblocks_supports_classname
lazyblocks_supports_ghostkit_display
lazyblocks_supports_ghostkit_spacings
lazyblocks_supports_ghostkit_scroll_reveal

Could you help me find how to do what I need to do ?
How can I call this Lazyblock URL I created ?
How to make it appears in the Custom Field name list of the grid plugin ?

Thanks for your help !!
Samuel