My first look at paper trading on Bitfinex, affiliate link https://www.bitfinex.com/?refcode=hHGnz8Oq-
Summary
The good
A safe place for new users to experiment with trading crypto
The bad
Limited functions at the moment
Need new email to set up, why?
Claim it is a good place to try trading strategies, it's not
Overall
I like it
I use brave browser it is pretty good, just like chrome except ads are optional and if you opt in you get paid for it. Here's a referral link that earns me a small amount
My favorite site for trading crypto is Bitmex, as the future contracts allow for lots of arbitrage opportunities and the leverage lets me leave most of my stash safe in cold storage. If you don't already use it and would like to sign up, here is a referral link
https://www.bitmex.com/register/wjyGH2
That will get you 10% off fees and rewards me with 10% of the fees you pay, we both win.
Similarly my favorite site for trading options is Deribit, Here is a referral link for that
https://www.deribit.com/reg-10009.1179
A few of the exchange sites I also use are binance, bittrex and hitbtc, I find them about as good as each other to be honest but these have referral links so I figure I'd shill for them.
Disclaimer
Please do not invest on the advice of a stranger on the internet, only use this advice here as a starting point for your own research, and then if you choose to invest please only invest an amount that you can afford to lose.