I've been into crypto for some time now one thing many people overlook is security as it is a fact that bitcoin is by far the most decentralised and secure coin, don't let anyone tell you any different on that respect.
There are very good alt coins but theres hundreds now and only some of these will stand the test of time, investing in the big 3 for longterm could be good stepping stone.
Bitcoin BTC
Litecoin LTC
Ethereum ETH
You will need to learn about wallets to keep your coins and always chose a wallet that gives you your private seed, this seed makes the coins yours and if you ever lose you wallet you can get your coins back by entering your seed into another compatible wallet.
There are hardware wallets which are the most secure and probably a very good choice if you are planning on investing an amount you really want to protect, I personally use Trezor but there is also Nano ledger s too. You will have to pay for a hardware wallet.
Paper wallets are really another for of hardware wallet ethereum have a great site called myetherwallett and or mycrypto (make sure you visit the correct site at all times, very important)
Always keep your private seeds to yourself and never share them with ANYONE.
Never keep coins on an exchange as you don't have the private seed and therfothe in reality you don't own them.
Research the coin you are interested in, the team, the project, the market, the competition, total supply, circulating supply and so on.
Be careful when on social media as there are plenty of bad actors shills and fuders, don't fall for anything they say do your own research (DYOR) I'll name one bad actor for you, Roger Ver claims BitcoinCash BCH is bitcoin (it clearly isn't)
Remember when transfering coins you can usually set your own fee to transfer especially with bitcoin and Ethereum and erc20 coins.
Erc20 are coins built on the ethereum blockchain these account for a lot of alt coins.
As an example some of my coins include
Bitcoin
Ethereum
Litecoin
Ethos
NEO
carVertical
Redpulse
Trinity
Quantstamp
UTrust
OMG
Monero
A good thing to keep in mind is decentralisation, bitcoin isn't owned by a company person or group it has the most divers developers and miners and has the biggest hashrate.
Ripple XRP is a centralised coin built for the banks that the bank doesn't use so investing in something like this carries risk as with any centralised coin, that doesn't mean it won't go up in value tho it just means the risk is it can go up I'm a puff of smoke.
Take care out there, your in charge of your own coins if you lose them or don't take precautions and get your coins stolen or loose your seed and wallet no one will bail you out, they are gone.
Crypto is here to stay and the blockchain will change the world. Good luck.