Why do you think I should run a Bitcoin core wallet while there are many wallet/exchanges like Binance and Coinbase? I know it's essential if you hold a bunch of Bitcoin.
Oh, wow, so first, you can't just bunch together
'wallet/exchanges', they're two very different things. An exchange is nothing other than a bank that lets you buy and custody some foreign currency for you. However, besides the privacy issues of buying
BTC through exchanges; if you actually use them as a wallet...
then you don't actually own your Bitcoin!
Have a good read about this topic here:
https://notyourkeys.org/So you
absolutely don't want to keep coins on exchanges.
But, I have such a tiny amount of Bitcoin (below $1K).
This doesn't matter. Running a node doesn't have a lot to do with holding your keys (
which again, is essential). You can use any open-source non-custodial wallet and be safe from your funds being stolen or confiscated, without having to run a node. In fact, that's what I recommend; since a full node is always online and that computer might be infected by a virus.
The reason you want to run a node is to make Bitcoin decentralized. If only the big exchanges ran a node, it would be trivial to attack the network. Blockchain is meaningless without a decentralized network.
I think I can hold them on Binance and stake it to accumulate more satoshi.
That's a terrible idea; you risk losing it all just for a tiny amount of 'rent' you get from it.
Are there any benefits of running a full node?
Yes; you can point your wallet software
at your own node in its settings, like Trezor software or Electrum. This will cause it to look up addresses and balances on your own local copy of the blockchain, making your Bitcoin usage much more anonymous.
I know that sometimes Running a lightning network node can give you some benefits which also not profitable (less than $1/month). Suppose I installed a full node. Why do I have to run it 24/7? What are the benefits?
Running a (Lightning) node is not for profit; that's because Lightning is made to be cheap and the routing fees are incredibly low. But that's by design. As I just said, the main benefit of running your own node (for you) is that you gain more privacy and you can't be fooled by a malicious block explorer. Such a site could lead you into the belief that a payment was sent, while it was not, for instance.
You don't have to run Bitcoin 24/7, but for Lightning it is required. The reason why is a bit outside the scope of this topic, but there are lots of good resources about it.
I have a Ryzen 3 3200G CPU+ 16GB Ram + 2TB HDD PC. Can I install the full node in this setup?
Sure; the whole point of the thread you've read here is that Bitcoin runs on super low-end laptop hardware. As far as I can tell, that's a pretty good CPU so it will work.