good that you ask. And yes, there's a general recommendation from the EBU (European Broadcasting Union) for loudness levels in radio, TV, for streaming, and so on. They have a bit of a technical paper here:
For our purposes, Youlean explains it in a way which is a bit easier to understand - and they also have a cost-free loudness meter linked in their page, one of many:
For here, and to make it short:
-23 LUFS and -1dB TP (true peak) is the cuurent EBU R128 recommendation for radio, TV, and such
-16 LUFS and -1dB TP is their recommendation for streaming services (like here)
Others, like Youtube, Spotify & Co go a bit higher (louder on average which also means lower on dynamics).
I don't know with which programs (and OS) you work, but you'll find lots of plugins, both commercial as well as cost-free or even open source ones for almost every DAW on the market.
If you'd like to spend at least 1$ (an amount of your choice), you'll get a compiled version of Ardour 6 (for Linux, Mac, and Windows) which automates this nicely - I can set my "target loudness" during export, or even export for different "targets" (like Youtube or Wikiloops) concurrently. Ardour can do this in several ways, I wrote about that here: https://wolfgang.lonien.de/2020/09/the-new-ardour-6-3-is-out-and-it-has-a-really-cool-feature/
For here, I try to stay at -16 LUFS and -1dB TP, but I know others that go a bit higher (like -14). Both of these leave enough headroom for peaks, and for the music to still sound dynamic.
Important by the way: don't go for the assumed "correct" loudness too early, and in each track - that is something you should care for in the end only (during "mastering"). While still working on tracks, it's much more important to leave enough headroom, so if your meters show something like -10dB (also for the imported tracks of others which you might even have to reduce a bit sometimes), it's just fine. In the end, and on the master channel give your mix the right level.
I hope that helps?