Call the stimulus hotline if you haven't gotten your First check yet. It may have been returned. They will tell you what to do. Do NOT go to the IRS website and click on the non-filers button if you eventually expect to file. This may force you into mailing your return and delay your refund significantly.
IF you typically self-prepare your own return, we respectfully advise you to go no more than 4 years without seeing a professional to avoid red flags and opportunities to get a greater refund. Particularly since 2018 with the new tax code and then again with all the new tax code changes due to Covid 19, now is the time to rely on a professional. Why see a professional every 4 years? Because you are only allowed to go backwards to collect increased refund money for 3 years through the amendment process.