While “this is the first time I see” makes sense, what a native speaker would instead say or write is “this is the first time [that] I have seen” or “this is the first time [that] I've seen”.
More generally, native speakers use a present perfect tense rather than simple present tense for “this is the nth time [that] <subject> <verb>”.
That peculiarity does not hold more generally without “this is” or “that is”; nor does it hold for past or future events.