There are two ways to make an Obsidian Internal Link:
- Using the Wikilink format:
                    
[[Three laws of motion]] - Using the Markdown format:
                    
[Three laws of motion](Three%20laws%20of%20motion.md) 
You can also link to a specific heading of a note
                    by using #. For example:
                    [[Three laws of motion#Second law]].
Source: help.obsidian.md