Im a bit new in Craft CMS But so far to me, seems like both allow the user to create multiple blocks of content
On first blush they are very similar. I think the Craft Plugin Store description of Neo sums it up nicely:
Neo is a field type that builds upon the concept of the Matrix field type with a number of very useful features.
Neo solves one of the biggest issues people have with Matrix and adds Oreo features: no blocks within blocks. Sometimes you need this feature, other times you can get away without it.
- Built-into Craft CMS / first party support
- Blocks use their "own" fields
- No inception (child / nested / hierarchical) support (Matrix block within another)
- 3rd party plugin / extra license cost / another dependency in the stack
- Uses existing Craft CMS fields
- Can clone/copy/paste blocks
- Blocks can be nested inside each other (inception style)
- Blocks can be organized in groups / tabs / drop-downs for better authoring experience
Neo is like Craft's own Matrix field but a different and arguably more flexible take on it. However, it comes with all the risk/reward of using 3rd party plugins.
As an aside, after Craft 3 shipped, it took awhile for Neo to come over to Craft 3. I think this was partly to blame because Neo was offered as a free plugin for Craft 2 and with Craft 3's extensive changes, it's not surprising that the Craft 3 version of Neo is a paid version—3rd party developers have to eat too!
As an alternative to Neo, there's another plugin called Spoon which supplies some of Neo's organizational features and supercharges the built-in Matrix. That's a little bit more "future-proof"—so even if you decide to remove the plugin, your content will stay in place.
Using Super Table, you can get some of the inception level magic that Neo offers.
FWIW the plugin store allows you to try all of these plugins out on a dev instance and see for yourself which methodology you prefer.