@imaltesers just to be sure , let me cover the situation as I understand ---
(a) you , a foreign citizen ( which country - Malta ? ) was admitted to the USA on August , xx, 2020
(b) you were in foreign country till that date ( ??) and had earnings from the foreign country
(c) you are married to an American citizen whom have earnings for the year 2020
Now the question is how should you file --- Married Filing Joint or Married Filing Separate; and do you need to recognize the foreign earnings prior to your entry into the USA .
First generally it is better to file Married Filing Joint -- it is more tax benign
Second, because you have the Green Card, you are therefore are treated as a resident for the year and subject to US tax on your world income. The question here is when is the start of your "year" --- generally it is the first full day that you were present in the USA during the tax/ calendar year. Thus if you have had zero US presence during 2020 before the entering on August XX, 2020, then you are Non-Resident Alien / Non-US person till that date and hence your foreign earnings are not taxable by the USA.
So for a clearer answer we need to know all your presences in the USA during 2018, 2019 and 2020 -- please provide --yes ?
