A client is asking for an EIN

You can give the client an EIN you get now for work done last year. 

A sole proprietor without employees and who doesn't file any excise or pension plan tax returns doesn't need an EIN (but can get one). In this instance, the sole proprietor uses his or her social security number (instead of an EIN) as the taxpayer identification number.

I had the same exact question as the one you answered.  So then—-As a sole proprietor, if I get EIN in Feb 2022, do I enter it somewhere on my taxes for 2021?   I was planning to use by SSN obviously.  
A client asked me for tax ID for his form 2441 for 2021.   If I give him the newly created EIN, wont it need to be on my 2021 tax return?

Next year, when I do taxes for 2022, will it matter that my EIN was created in Feb (and not before year started) in terms of completing the return with SSN and or EIN?

thank you 

Yes, you will want to enter the EIN on your 2021 tax return. According to the IRS, the EIN can be used for this tax year, but it can take up to two weeks to become part of the IRS's records, so you will need to wait that long before filing your return. To enter it on your 2021 return:

1. In the Federal > Wages and income section, scroll down to Self-Employment and click Start/Revisit next to Self-employment income and expenses.
2. If you have already input data for your business, you will want to click Edit on General Info.
3. Scroll down to Employer ID Number under Payments and identification and click Edit.
4. Enter the EIN you were provided by the IRS. The fastest way to get one is by applying online.