When you multiclass, spell slots are determined per the multiclass spellslot chart. So for ranger and paladin you take half your level in each rounded down - So 6 for ranger and 3 for paladin. That means you have the same amount of spell slots as a 9th level multiclasser. Coincidentally that is the same spell slots as a 17 level ranger.
I have a multi-class character Ranger 13 and Paladin 7. When I go to my spells it's thinks I'm like a level 17th level Ranger with the spell slots.
When you multiclass, spell slots are determined per the multiclass spellslot chart. So for ranger and paladin you take half your level in each rounded down - So 6 for ranger and 3 for paladin. That means you have the same amount of spell slots as a 9th level multiclasser. Coincidentally that is the same spell slots as a 17 level ranger.
Wait really, I didn't know that thank you.
You should read the whole section on multiclassing if you are going to do it. Lots if things apply differently when you are multiclassed:
https://www.dndbeyond.com/sources/phb/customization-options#Multiclassing