"I don't want the high from the THC. Everclear is not available locally, can I use tequila to make a tincture?"
The higher the alcohol proof, the more it will extract the compounds out of the plant. In order to get the CBD that you are looking for, yes, it does need to be decarboxylated in order to convert the CBDa (an acid) over to CBD (cannabidiol). If the 190 alcohol is not available then a 80 proof alcohol will have to do!