If your business made a profit, you can contribute to a SEP-IRA. You can also contribute to a regular traditional IRA. Depending on your MAGI for the purpose, you might also be eligible to contribute to a Roth IRA. You have until the due date of your 2020 tax return (now May 17, 2021) to establish any of these and contribute.
Since you file jointly with your spouse, your spouse can also contribute to an IRA (by May 17, 2021) if there is a sufficient amount of your net profit remaining after subtracting the deductible portion of self-employment taxes and your own retirement contributions.
Be aware that any deductible regular traditional IRA contributions an individual makes for the year they reach age 70½ or thereafter affects their ability to exclude from income a Qualified Charitable Distribution.