Let's say you want to haggle a better price at a shop.

You can start by explaining that to your DM.

They might ask how, and you can just generally describe what you'd like to do.

Not sure how to explain? Ask the DM to better describe the shop or individual.

Then pick something, maybe they have a sweet hat, or a cool earring. Maybe the store looks really clean or maybe all the other patrons are dressed fancy. Maybe you can investigate the craftsmanship of the weapon or shield and compliment the shop owner.

The important thing is you pick something, it doesn't matter what. Maybe that earring you commented on is a family heirloom. Roll well and the shopkeep is reminded of their family an gives you the family and friends discount. Roll poorly and the shopkeep is reminded of how their family was brutally murdered and they ask you to leave.

That's not everyones strengths, that's all! Just play to 'em! Like I do voices for all my characters because I can. Most of the time other people in the group don't do voices because they feel like they can't or feel uncomfortable. That's cool! No ones pressuring them to do a voice just like no ones pressuring me to not do a voice. That's the great thing about dnd. Everyone gets to have fun!