The software will ask you about your marital status and if you want to file your return and your spouse return together, if you marked that as yes and finished your profile, you will not be able to remove your spouse to file a separate return.
However, you can complete both profiles and file only your return on in the file section. On the payment page you will need to pay for each return completed.
If you want filing a separate return as married, you will have to report your spouse net income so the software can determine the eligibility for federal and provincial credits and benefits.
Moreover, if you completed your return together last year and want to file separately you will not be able to transfer the information from last year. You will need to start a new return from scratch and when asked if you would like to do a return for yourself or for both you and your spouse, you'd choose the appropriate one.
If your marital changed, you can find more information from following Links-
How does a change in marital status affect my tax return?
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