In addition to @anon6471198 's suggestion, I would add another one:
Ubuntu-cleaner.
Everything has its pros and cons. Bleachbit is more verbose and selective in your choices. Ubuntu-cleaner does not need to be differentiated as root in order to use it and is thorough and very easy to use.
Both are quite safe.
I would give Ubuntu-cleaner an additional point for safety, however. As Bleachbit offers more select-ability of what you are removing, a user can accidentally wipe data they didn't want to lose.
Which... may relate to the warning above to use it responsibly.
When I was a Windows user, I used CCleaner. I would consider the above two choices similar in function and usability to familiar CCleaner, but more thorough in action and results.
Installation:
Ubuntu-cleaner is independently developed and open source, so resides in its own repository:
sudo add-apt-repository ppa:gerardpuig/ppa
sudo apt update && sudo apt install ubuntu-cleaner
I have used both since I moved over to Linux and never had either of them fail me or behave buggy.
There was one small gripe about Bleachbit that I had in which it places two panes very near to eachother overlapping the checkboxes: you can read this guide here to solve that: