Drag to select. The text is copied when you let go — there is nothing else to press.
Double click selects (and copies) a word; triple click a line.
Drag past the top or bottom edge to keep scrolling while you select.
Esc clears the selection; y copies it again.

Copying is smart about the two things terminal readers usually get wrong:

Code blocks copy without their frame and left margin, so what you paste is the code, ready to run.
Paragraphs that were wrapped to fit your window are joined back into the single line they were written as.

A notice says how much was copied (✓ copied 57 characters).

Copying happens over two routes at once: the standard terminal clipboard sequence (OSC 52, which also works over SSH) and a system tool when there is one (wl-copy, xclip, xsel, pbcopy; on WSL, PowerShell or clip.exe). Your terminal gives no confirmation of its own, which is why wr shows the notice.

If you would rather select with your terminal’s own mouse selection, hold Shift while dragging, or turn Mouse support off in Settings. If you prefer to select first and copy on purpose, turn Copy on select off: the selection stays highlighted and y copies it.