Never bothered with etoro so can't comment, i use coinbase pro, Binance, Gemini and Kucoin and have never had issue with any. If it is just BTC LTC you are after then It's as easy as transferring flat to a coinbase account, then moving your funds at no cost to coinbase pro and trade the BTC/GBP pair.
I should download them all and open an account now as the approval process can be long winded. You don't want to be stuck unapproved when a good opportunity comes along !
Buying can get a touch more complicated if you want lesser known coins...happy to expand if needs be
I use coingecko and thecryptoapp to generate price alerts and typically coinbase for general price analysis. ( Crazy fees don't buy on there..)
If you only start with small amounts I would not worry too much about keeping the funds on an exchange but for heavy amounts consider a wallet...
Hope that helps as a starter !
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