The number of messages you can send depends on how old your WhatsApp account is. If you have a new number, start by sending a small number of messages like 50 per day. Gradually increase it by around 5-10% every day and within a month you can reach up to 3000-4000 messages. WhatsApp will ban your number if you send too many spam messages. This happens if a large number of people report you as spam. So always ensure that you don’t spend spam especially from a new number.