Will pumping END to 10 at level 30 gain the same health as leveling to 30 while having 10 END?

Probably. Someone who's watched spoiler footage might know for sure, but from what I can tell, max health is calculated as 100 + 5 * Endurance (plus relevant perks). That's just from looking at the Pip-Boy app, where the demo mode's character has an Endurance of 3 and 115 health at lvl 6. But even if that's wrong, Maximum Health will probably be calculated as a function of your endurance and relevant perks, no matter when they were selected.

how does health and endurance work in fallout shelter because im pretty sure thats how it will work in fallout 4

Endurance has to be 10 at level 1, for your dwellers to reach full potential.