Welcome from El Reno, Oklahoma
#1. Yes you can (25 years old or older) but you will be severely limited on when and where you can drive. Oklahoma is pretty picky about using a antique/classic registered/tagged vehicle for daily driving. You can probably get insurance by contacting your current insurance agent directly and describe what you have and it’s intended use. If he/she can’t help you can go with Hagerty or one of the other specialty insurance companies.
#2. We can’t help with that unless you tell us what engine your truck has.