Installers for all supported operating systems are already out. QGIS 3.18 comes with tons of new features, as you can see in the visual changelog. Additionally, QGIS 3.16 ‘Hannover’ has now replaced 3.10 as LTR.
QGIS is supported by donors and sustaining members. QGIS is Free software and you are under no obligation to pay anything to use it – in fact we want to encourage people far and wide to use it regardless of what your financial or social status is – we believe empowering people with spatial decision making tools will result in a better society for all of humanity.