There is no requirement to trade every day. However, you must be aware that FTMO deletes trial accounts that are inactive for 48 hours after creation. Once an account is created, you must begin trading within 48 hours or the account will be deleted and the attempt counted as used.
You should also check in on the Telegram group weekly and log your weekly roll-call attendance, as this affects your eligibility for larger funded accounts ($50K–$100K).