Breaking both down we have 3 things to take note of:
i5/i7 - indicates relative performance or feature set within a given generation, bigger is generally better
13/7 - the generation of processor
600/700 - where Intel rates a given processor within a generation, this is consistent and doesn’t (to my knowledge) involve overlap between i3/5/7/9 - generally bigger is better.
So i5-13600 is a thirteenth gen i5, type 600. i7-7700 is a seventh gen i7, type 700
Then you get the legion of letter suffixes determining other features, mobile SKUs etc.
What used to be the i7 was (like with the i7-7700) now occupied by the i9 line
The value price of the 12600k is just much better
i5-13600k is around 38000 points (https://www.cpubenchmark.net/cpu.php?cpu=Intel+Core+i5-13600...)
i7-7700k is around 9600 points (https://www.cpubenchmark.net/cpu.php?cpu=Intel+Core+i7-7700K...)
So the new i5 is nearly 4x faster than the old i7. New CPUs have come a long way over the last few years.
Looking up the numbers instead of reading them like tarot cards, I can tell you that the i7 7700 is a 8 core processor with a max turbo frequency of 4.20 GHz, and the i5 13600 is a 14 core with 6 cores that can do 5 GHz, and 8 efficiency cores capped at 3.7GHz. And both support VT-d, which is about the only feature I would care about :D
In general, you can only infer very little from the marketing names. To have any actual idea, you have to look at benchmarks. In practice, 13600 is ~70% faster per thread, and has 2.5 times the threads.