NOT in country and NO income so Tax returns as 'Resident Alien' possible?

[Kudla]

I got my GC in 2014 and applied and received Re-Entry Permit and was out of states for 2 years.

I do NOT have any income to show for the years from 2014 until 2018 now in US or elsewhere.

Do I have to file taxes even if there was NO income?

If so, should I file 'zero returns' tax for the years I was out of the country as 'resident alien'?

Please do advise!

[newacct]

I got my GC in 2014 and applied and received Re-Entry Permit and was out of states for 2 years.

I do NOT have any income to show for the years from 2014 until 2018 now in US or elsewhere.

Do I have to file taxes even if there was NO income?

If so, should I file 'zero returns' tax for the years I was out of the country as 'resident alien'?

Please do advise!

You are not required to file if your (worldwide) income that year was below a certain threshold.