1 and 2 -- Yes, both are fine.
3 and 4 -- These are technically correct statements, but not to be used in public or even some private groups. Usually, people say one of these in formal situations:
I need to use the men's room.
I need to go to the ladies' rest room.
1. It is the year 2019.
2. It is 2019.
[Are both okay?]
3. I have to urinate.
4. I need to defecate.
[Are these expressions formal and polite expressions?]
2 answers
im feeling akward... meow meow