A language parent is a native speaker of the language who is willing to communicate with you regularly, with a lot of patience*.
You will also imitate their speech in order to speak like a native. By imitating one single person, your accent will sound like a real native rather than a strange foreign mixture.
If you have a partner, a friend or a colleague who is a native in the target language, they might make a good language parent (one word of warning if you choose your partner: it requires a lot of patience from them which might put stress on your relationship!).
Online friends also work. Check Facebook or Discord communities in the target language and befriend someone!
If you don’t have that, you can get a private (online) tutor. Make sure you try a couple of tutors to find one you really like, since this will be a long term relation and you will spend a lot of time together.
Make sure you like the way your language parent speaks, as you will develop the same accent and manner of speaking!
When speaking with your language parent, they will use their utmost effort to try to understand what you’re saying, they will NOT correct you unless you ask for it, instead they will confirm their understanding with a correct native phrase.
Example conversation (confirm with your potential language parent that they’re willing to have this kind of conversation with you):