1. Click the position where you want to enter π with the mouse, right-click the floating window of the input method, and then click "Expression &; Symbol "button:
2. Click "Expression &; Click the "Symbol Collection" button in the "Symbol" option to enter the symbol selection interface:
3. Click the "Greece/Latin" button on the left side of the symbol interface, then find "π" in the symbol on the right and click the "π" button:
4. At this time, "π" will be inserted to the position clicked by the mouse before, and then press enter to confirm the insertion: