How much ram/vCPU cores do I need to run my website? IYO

Pretty basic, RESTful API connected, survey site with a login feature

Cpanel installed,

We expect 100 daily users first 6 months.
500 within a year.
1000 within 2 years.

Could anyone gauge how much ram, and how many cores I would need at each of these amounts?
I apologize for being such a Laymen.
Thank you

EDIT:

Updated figures 5,000 in 6 months, 25,000 in a year, 100,000 in 2 years.

User spends on average 2-5 minutes on site,
First 2 minutes actively clicking on things, last 3 looking at results.

Please preface response with ‘READ FULL’
So I know you are answering second part!