Welcome to the community !

I guess this is your home work and it’s not really related to any particle devices

But let’s start.

Firstly to calculate your R1 value you have to know the Ohm law and understand it 100%

secondly the value of Vds can be close to Vcc (transistor closed ) or (when the transistor is open) can be calculated base on the parameter

Rds-on which can be found in datasheet here

Let’s back to Ohm law so we know that I=U/R so the R=U/I so your final equation should look like this R1=Vcc-(Rds-on * I)/I

Rds-on * I is your Vds where transistor is open Finally

R1=3300mv-(Rds-on*70mA)/70mA

You just have to find out the Rds-on from the table

Please note I changed 3.3V to 3300mV as this is really important and is easier then changing mA to A

Best,

Arek