I started Turbo Tax this year via Safari , not the Turbo Tax App. Will this mess things up? Do I need to switch my data to the App? If yes, how do I do that?

[Critter-3]

If you used the downloaded/cd version last year and will use the online program this year then when you first start you can transfer the prior year info at that point ... follow the onscreen instructions.

[VolvoGirl]

Do you mean the Mobile App or the Desktop installed program?  If you used the Desktop program you need to have the file ending in .trax2020 on your computer to transfer into the Online browser version.  Do you have that file?  Or do you want to use the Desktop program this year?  We can tell you how to switch.

How to Transfer into the Online version
https://ttlc.intuit.com/community/entering-importing/help/how-do-i-transfer-last-year-s-return-into-...