Which booster does cell as well as data

Our Maximium Signal Max Amp RV booster has worked well for us for both voice and data in a number of areas where our phones and hotspots indicate no signal or a very weak signal at best without it. But to clarify, the cell services are used for both voice, text, and data, although the different modulation formats used for standard voice and data are often on different "bands" or frequencies. That may account for differences in voice and data reception. Text sometimes works when voice on the same signal does not, simply because text uses a relatively simple data format that's easily error corrected on the fly compared to the much more complex voice formats. Error corrections add an unnoticeable delay to the reception of the text message, but that same delay would be completely unacceptable in voice calls.

Here's a good write-up from Technomadia on cellular boosters:

https://www.rvmobileinternet.com/resources/mobile-cellular-boosters/

Depends on your booster
The older early models cover less 'bands' , than the newer models
The booster doesn't know what is being carried by the signal
It either covers the band you need or it doesn't
Your problem is your to far from the tower in a Busy area
Using a booster getting you a better connection to the tower may help
But the connection might still be slow, solid but slow, because of the amount of cell traffic during the day

voice and text is almost always, maybe always on a different frequency than data. Therefore, what you experience is not that uncommon. the frequencies are far enough apart that propigation characteristics are different and distance, obstructions etc. have different effects on the signal.

We camp a lot where cell signals are marginal or non existent without a booster. With a booster there are spots where I can get data and voice, data only, or voice/text only.

and there are times where I can get or send a text, but trying to call often results in a dropped call or marginal call.

most new boosters will do voice and data. For a while older boosters didn't suport 4G and/or needed a specific booster for either CDMA carries or GSM carries.

Newer boosters seem to support 3G and 4G for both systems now.

Now, given that, if your in need of a boosted signal, there is a good chance your still in 3G territory, so even if you get data it may be slower at 3G rather than 4G rates.