Arguably the metaverse is one part of a larger reformulation of network based human activities called web 3.0. People call it that following the tradition of demarcating large shifts/upheavals in networks and how people use them.
Web 1.0 is generally considered to be the earlier days of the World Wide Web (www) and consisted in mostly static websites that were based primarily on one way communication (communication flows from the creator of the website, to the website viewer).
Web 2.0 is generally considered to begin with the rise of social media platforms, perhaps starting with chatrooms, BBS, irc but really coming into existence fully with MySpace, FB etc. Web 2.0 is formulated around two-way communication and user generated content.
So what is Web 3.0? Its not clear yet because different individuals, groups, corporations, maybe even governments have different interests and visions for the future of networked communications/human interactions. What is clear is that we seem to be at the start of another big network paradigm shift. This shift potentially involves changes in the way information and digital assets are produced, owned, distributed, and accessed, as well as shifts in the architecture of cyberspace.
I would argue that blockchains/smart contracts, distributed filesystems (ipfs, i2p), and DApps are going to play a significant part of web 3.0. If you want a good place to start, check out the free intro courses at coursera.
Regarding the things you mentioned:
The metaverse is a speculative part of web 3. Its primarily conceived of as VR/AR tech. Personally, I think full integration of VR into daily life is a fairly long way off. AR may be closer, but the tech has been around for a long time and hasn't really caught on.
Moralis is a DApp development platform. It may be a good place to go if you want to launch/scale a DApp, but you'd be better off learning the basics of JavaScript/Node/React.
Solidity is the language commonly used for writing smart contracts. Learning it is important if you ever want to build a DApp.
Check out the pinned comment over at r/ethdev for some additional resources