To make the text truly fit that "Posty" aesthetic, keep these elements in mind:

If the beat has a guitar loop, lean into a more "folk-trap" vocal delivery.

"Ice in the glass, watch it melt to the floorI don’t even know what I’m fighting for anymoreTwo-door sliding through the city like a ghostThinking ‘bout the things that I probably miss the mostBut the champagne’s cold and the ceiling’s goneI’ve been awake since the break of dawnEverybody’s talking but I’m tuned outThis is what they never told me ‘bout..."

Here is some original text (lyrics/hooks) you can use or adapt for this specific style:

Search for "[FREE] Post Malone Type Beat Out of Mind" to find producers like Penacho or RellyMade.

This is the standard for buying high-quality, untagged versions of these tracks from independent producers.

Are you planning to with this beat, or are you just looking for captions for a video featuring the music?

When recording, use a wide vocal vibrato and simple ad-libs like "Yeah," "Ayy," and "Whoa." Where to find this specific beat?