Use the "Inset" (negative offset) feature multiple times to create internal lines that fill the letter, or use the "Offset" feature to create a border, then fill it.
Ensure the pen is pushed down completely into the 'A' clamp until it clicks. To give you the best advice, could you tell me: 745918
In the font dropdown menu, select "Filters" and check "Writing" . Use the "Inset" (negative offset) feature multiple times