Fitness for almost two years, what should I do if my strength has not changed?

That must be your wrong exercise method. You need a professional to give you a systematic plan, and you haven't said your exercise method, and I can't point out what's wrong. So I'll give you some advice. Play with your hands and make clear your training goals. All the movements today are back exercises. Other parts should be practiced; Plan the time, control each training time to one hour, and rest between groups for 30 to 120 seconds. Do not play mobile phone nonsense during fitness time; Actions should be exhausted, even beyond exhaustion. This will be effective; Action standard, specific can be found; The most important thing is to get enough sleep, eight or nine hours. Because muscles grow after you fall asleep, not only can you not grow muscles, but you may lose weight.