Can I take my money out of E-Trade?

Excuse me, could you please clarify something for me? I've been reading about cryptocurrency and investments, and I came across a situation where someone was asking if they could withdraw their funds from E-Trade. Now, I'm curious about the general process and what's involved in taking money out of a platform like E-Trade. Do they have any restrictions or fees associated with withdrawing funds? Is there a specific timeframe in which the funds become available after initiating a withdrawal? And lastly, are there any best practices or considerations one should keep in mind when deciding to withdraw their money from such a platform? I'd appreciate your insights on this matter.