Macros - Grid - Open source - Web version

This is the first time I use the forum and hopefully I do it in right way.
I’m interested in writing macros in Grid, but my knowledge is very poor.
Question 1:
Please advise where I can find some tutos, manuals, courses, or other to learn the structure, the synthax and so on for javascript in Onlyoffice.
Question 2:
I want to write a macro which is able to copy a cell from sheet 1 to a cell in sheet 2.
Please advise how to do.
Thanks in advance for support.

You can find the documentation about writing macros for ONLYOFFICE editors here:
As for copying cell value to another sheet, we don’t have any example macro, but you can use methods described here:

Thanks for quick reply Carl.

please. Can methods described here:(ONLYOFFICE Api Documentation - Structure of a spreadsheet) be used to write macro or plugins code? I know they are docbuilder API.

Yes, macros for spreadsheet editor can use these methods.