How do i try out filing jointly and filing separately without losing all of the data I've entered online?

You cannot use the same return or same account to try out MFS and MFJ.  It will be a mess.

It is not easy to compare MFJ to MFS using online TT but you can do it.  Since you only get one return for each account and user ID, you have to use 3 accounts and user ID’s—one for MFJ and two for each of the MFS returns.  Compare, choose, and file—and pay—accordingly.

It is much easier to do this comparison using the desktop version of TT installed from a CD or downloaded to your own computer.  You pay once for the software and you can prepare multiple returns easily, and it has a “what if” feature that allows comparisons.

If you were legally married at the end of 2022 your filing choices are married filing jointly or married filing separately.

Married Filing Jointly is usually better, even if one spouse had little or no income. When you file a joint return, you and your spouse will get the married filing jointly standard deduction of $25,900 (+$1400 for each spouse 65 or older)  You are eligible for more credits including education credits, earned income credit, child and dependent care credit, and a larger income limit to receive the child tax credit. 

If you choose to file married filing separately, both spouses have to file the same way—either you both itemize or you both use standard deduction. Your tax rate will be higher than on a joint return. Some of the special rules for filing separately include: you cannot get earned income credit, education credits, adoption credits, or deductions for student loan interest. A higher percent of your Social Security benefits may be taxable. Your limit for SALT (state and local taxes and sales tax) will be only $5000 per spouse. In many cases you will not be able to take the child and dependent care credit. The amount you can contribute to a retirement account will be affected. If you live in a community property state, you will be required to provide additional information regarding your spouse’s income. ( Community property states:  AZ, CA, ID, LA, NV, NM, TX, WA, WI)

 If  you are using online TurboTax to prepare your returns, you will need to prepare two separate returns and pay twice.

https://ttlc.intuit.com/questions/1894449-married-filing-jointly-vs-married-filing-separately

https://ttlc.intuit.com/questions/1901162-married-filing-separately-in-community-property-states

https://ttlc.intuit.com/questions/1894449-is-it-better-for-a-married-couple-to-file-jointly-or-separately

If filing online, you need to make three accounts with different user names and passwords and start over fresh for each one (MFJ, spouse 1 MFS and spouse 2 MFS).  (You can use the same email address for all.)

Or you may want to purchase Turbotax desktop version to install on your own computer from a CD or download, you can transfer your data file too.  There is an MFS/MFJ worksheet in the desktop program but not online.

It's pretty rare that you would save money filing MFS and I don't think we've ever seen the program recommend this.  It would be interesting to know more about your situation, can you post a screenshot of the recommendation?

In the forms section of turbo Tax there is a what if. Click that and it will break the returns out separate to give you a better idea which way is best.

Then start a new return for each of you to verify that it is better