I am going to install virtualbox on tails, but I couldn't find any good tutorial on this.
Please help me.
If anyone met any solution for this, any help will be appreciated.

It's very easy. Not sure if you need tutorial for this.

first create container and after install there

Create a machine, just add the tails iso in the storage disc and fireup the system.
Simple as that.
If you want persistence then its different story.
peace
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