What would be the best first time credit card to use for gas and best way to use and pay it off monthly?

I'm a 32 yo male who has never had a credit card. I was just taught the old school way of "if you can't afford it then you don't need it" so I never had much of an interest or need in one. I'm an authorized user of my parents to have a credit score but don't use or have my own card. I only have an Experian score but it's at 775 thanks to the AU of my parent's. On credit karma it says another line of credit would help my score since I'm only on the one cc.

With that said, I want to open my own cc and use it for gas once a week or so to try and build some credit on my own. What would be the best card for me to start with and how is the best way to use it? Do i just pay the full balance at the end of each month? I'm new to this and would appreciate any help and guidance. Thanks for any help ahead of time!