Min I would say is about 3-10k find which exchanges you want to use like binance, coinbase, or poloneix.
3k usd?
What are you talking about, why would he require so big amount of money to begin trading?
Don't spread misinformation.
How many dollars i must have to begin trading ?!
You can start trading cryptocurrencies with very small amounts like 100usd maybe even less depending on the exchange.
Binance is a good one. Just make an account there and see what is the minimum order in btc. It is probablybelow 100 usd, I don't know exactly.
For sure it's not 3k