If you are creating a landing page and want custom links in the Menu that point to different blocks in the page, here is how to add them:
Step 1. Go to CMS (hamburger icon)> Project Settings - Menu tab
Step 2. Select the menu you want to add the custom links to, from the drop down
Step 3. Add Custom links from the sidebar.
Step 4. Click on the Settings icon and add the anchor link in the Anchor field. For example, if you have named the Contact block as Contact, your anchor link will be #Contact.
In the Page Title field, please give a name for your anchor link. Your website visitors will click on this name to go to the specific block. Click on 'Save Changes' at the bottom to save your menu.
The block name is the name you give to your block from the block advanced settings.