It depends on what you mean by “pseudocode”.
Most people just mean that it is generally simpler and more natural-English-looking, with relaxed syntax when compared to “real” code.
Generally in that case I would use something like run_at_start and run_30_times_a_second to cover what Unity does.
However if you have a specific definition of “pseudocode” that you have to adhere to then it may not have something that is applicable.
solved What would void Start() be in pseudocode [closed]