Hello, I found some sites tagged as “royality free music”, but when I click on any music, I see only type, BPM and duration. It does not look relitable.
Please don’t quote me on any of this. I am not a lawyer. I’m pretty sure that anything in marketplace that you legally obtain and use properly is royalty free. I also believe that Unity store assets can be is used in Unreal and vice versa so you will have options if you can’t find what you need. Soundly I believe it’s called usually has a free trial near the UE4 game jams and from what I can tell it’s a subscription service with sounds (should be royalty free otherwise it wouldn’t make any sense to subscribe)
free music archives has a pretty extensive library, but they’re not all royalty free, most on creative commons.
https://freemusicarchive.org/
Otherwise there’s also https://archive.org/ most of the stuff there is public domain.
Oh wait, royality free mean not free? 
1 time pay, and then unlimited time use? Why then when I googled: “Free music for games” I get royality free sites …
There is a 5% royalty fee (with limitation) for any game you derive from unreal engine. But the eula probably span over the marketplace assets as well which you can obtain from unreal asset store. What it means using this cotnent in an otherwise unity game could be an issue after thorougly scrutinizing this end user license agreement of Epic EULA - Unreal Engine.
So what do you make out of a line like this? You must give this eula to a well prepared lawyer, and they will tell you what you are allowed to do with marketplace contents.
Also, royalty free doesnt allow you to use a given content for any purposes, in fact license agreements will limit your use cases - which you are probably mean by the “and use properly” and that is indeed the only way you are allowed to ‘properly’ use a content, by following the licence agreement’s guidelines. Any work, wheter it’s art or programming (and so on) is someone else’s creative work, and the property right (ownership) just cannot be handed over to many users, and as such you always fall under limitations regarding it’s use. It’s not yours basically. But you can for example use it to include in unreal games, since the epic eula is designed with this purpose in mind.
You should not mix licensed (and royalty based) contents since it could make your project budget bleed out the income pretty fast, not to mention the incompatibility of different eulas which is happen quite often. It’s better to stick to unreal marketplace for your unreal based game, and optionally you can try well worded marketplaces (such as envato for example) who are legally stable source of content. You can’t say the same for many other suspicious looking websites offering contents for cash, that doesn’t give you the rights to actually use them for anything but self entertainment at tops.
I am not a lawyer.
Looks like the best option is to do all by yourself I learned Art Rage and Blender, now explore Unreal Engine, and now will look for music creation program