I did this but still blurry, even after updating the text manually.
window.setView(sf::View(sf::FloatRect(0, 0, event.size.width, event.size.height)));
width = windowWidth;
height = windowHeight;
changeBrushText.setString("Change Brush");
changeBrushText.setFont(font);
changeBrushText.setCharacterSize(width / 96);
changeBrushText.setFillColor(sf::Color(210, 210, 210));
changeBrushText.setPosition(((width / 10) - changeBrushText.getLocalBounds().width) / 2,((height / 27 ) - changeBrushText.getLocalBounds().height) / 2);