Can't setting the menu like in demo site.com/#service

Hallo, I see the demo of https://colorlib.com/illdy/ and when I install to my site, I can’t add menu like https://colorlib.com/illdy/#services . When I add to mine like https://mysite.com/#service it can’t go to the service section. and I don’t see the documentation too. can you give me advice please ?
Thank you,

Hello there,

I hope you are doing well today.

Pleas ensure that you are using the correct spelling for the link, it should be “#services”.
Could you please provide a link to your website so that I can inspect it?

Best Regards,
Support