No, you do not have to bet every time in roulette. When playing roulette, you have the option to sit out and watch the game, or to simply bet on certain spins and skip others.
In fact, many experienced roulette players often take breaks from betting and watch the game for a while before placing their next bet. This can help them observe patterns or trends in the game and make more informed decisions about their next bet.
However, if you're playing at a physical casino, it's important to be aware of the table rules regarding minimum bets and minimum number of bets per hour. Some casinos may require a minimum number of bets per hour, or they may ask you to leave the table if you're not actively betting. So, it's always best to check with the dealer or the casino staff about the table rules before playing.