In the primaries you choose which party and choose your favorite candidate, and if there is a runoff you can only vote in the same party, you can't switch over to boost someone on the other ticket. In the general election there are no such restrictions. A "straight ballot" was sometimes an option - at the top you could darken the box for all Democratic or all Republican candidates, but that was taken away in Texas because some of the down-ballot Republican candidates lost when that happened when Biden was elected. (We have a really awful GOP governor right now.)

I use information from the League of Women Voters (a long-established non-partisan voter rights group) that gives each candidate in all local, county, state, and national races a place to fill out their information and state their policies. https://www.vote411.org/. Once upon a time there were publications with all of this information, now you have to go online to find it.