Animation Tab

I assume that you mean the Animation Workspace. Go to the top of the interface/Windows/Workspace/Animation.

I hope that this helps.

As already advised, resetting your workspace should be the first thing to do. For future reference it may also be useful to use the correct terminology so people understand what you actually mean:

https://helpx.adobe.com/after-effects/how-to/aftereffects-workflow-terminology.html

If you have specific issues not covered by these suggestions you have to provide more info.

Mylenium

Animation Tab?

Do you mean the Timeline panel?

A couple things might work.

• All panels can be found in the Window menu, so Window > Timeline.

• Try resetting the workspace. Windows > Workspace > Reset "name of current workspace" to Saved Layout

• If you closed the composition. In the Proejct panel, double–click on the name of the composition. That will reopen its timelne.

For questions like this, next time a screen shot would be helpful.