A basic privacy statement and contact email are given at info.cleanapk.org, but it is much shorter than ttps://e.foundation/legal-notice-privacy/ for example.
Who is the legal organization behind cleanapk.org? What law applies, French, German, Indian, other?
What is the postal contact address and name?
Should I install apps from an unknown organization so shrouded in mystery?
Please use the details on their site to contact them for this information.
We have tried to answer questions about Apps in the FAQ there are no further clarifications that are available from our side . This issue was discussed in detail here
If you are still not confident please use any other repository like FDroid or Aurora store or any other which you feel is secure for your app downloads.