Electrical

Alright, I don’t know a ton about electrical, but I got my 96 f250 earlier this year and I’m running into an issue. My left turn signal isn’t lighting up and I spent the last little bit cutting the old splice that was in and testing the volts with the blinker going, I’m getting 9-13 volts when using my meter but when I hook up the tail light socket my bulb isn’t flashing for the blinker. Then during this whole ordeal, while trying things out my running taillights no longer kick on. I’ve tried to search everywhere to find the fuses related to the running lights and all of the fuses I’ve checked are fine. I’ve become stumped regarding electrical and I don’t know what I’m doing wrong hooking it up. I appreciate any input