In order to access a return prepared using TurboTax you need the account and user ID to look at the returns.
If you and your spouse are filing a joint tax return you have every right to know what is on that return. Your name is being signed to that return, making you legally obligated to any tax owed. Sounds like you have some big issues in your marriage if your spouse is concealing income information from you and you might want to seek some legal advice---which we do not provide here.
If past returns have been filed as joint returns, you should be able to get copies of them or get transcripts of them from the IRS and I highly recommend that you do so asap. Establish an online account with the IRS.
https://www.irs.gov/payments/your-online-account
https://www.irs.gov/individuals/get-transcript
https://www.irs.gov/pub/irs-pdf/f4506.pdf
several other options but the best option is an attorney
1) after he files and the return is fully processed, you can get a copy of the return by filing form 4506 or a transcript by filing form 4506-T. Getting a transcript online may not be possible because you'll lack the needed information
2) you can deny your spouse the right to file a joint return, but then you would have to file your own return with filing status Married Filing Separately. It would then be illegal for him to file a joint return without your consent
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