I get a lot of text messages for work and I can't always reply or don't have an answer right away. Is there a way to flag conversations or specific messages for follow up at a later date?
There's not really any way natively. But you could use an iMessage sticker app to place a sticker on individual texts. Some you can create your own sticker. I used Word Art to place this thumbs up on a text message:
I don't know any other way to mark texts for future reference.