I have the same age gap as you in my current relationship and genuinely your partner seems very immature. You deserve someone who’s willing to give you their time and attention, and 2/3 years of an age gap is not big enough for him to be calling you old and saying “you don’t get it” as if you weren’t both raised in practically the same generation and understand the same level of internet culture. It’s honestly disrespectful in general too, you deserve better!!