Rabbi Herschel Schachter explains that in the current circumstances one must still do shnayim mikra.
Others have raised the suggestion that since presently we are not attending minyanim and not hearing Keriyas HaTorah, we should also not be obligated to perform the weekly mitzvah of shnayim mikrah ve’echad targum (to read the parsha twice with one commentary). The language of the Gemara Berachos (8a) is that shnayim mikrah must be done “together with the community”, and today there is no local community reading Keriyas HaTorah in shul. This is incorrect, and in fact just the opposite is true. The opinion of the Ra’avan is that the requirement of shnayim mikrah was specifically formulated for those who are alone and can not attend shul to hear Keriyas HaTorah. While the accepted opinion is not like the Ra’avan, and even those who attended shul and heard Keriyas HaTorah must still perform shnayim mikrah, all would agree with the Ra’avan that the obligation of shnayim mikrah should still continue to apply even when the local shuls are closed.
Rav Heinemann of Baltimore points out that even when, as now, no one can be in shul, one should read from the chumash as a zecher to the reading, including the haftarah.
One is not יוצא when he lains from a חומש. However, there is an ענין to have a זכר of laining and read from a חומש. This applies to the הפטרה as well. It does not hurt to read פרשת החדש as well. We find that they lained הפטרה when they could not lain from the תורה.