Clogged Cat. I think.

Recently been loosing power when getting up to Higher RPMs. Sometimes the engine just doesn’t respond when I press down the accelerator too. Someone mentioned the catalytic converter and i thought that as well. OBD only shows p0135 the O2 sensor. haven’t been driving it much bc I’m scared it will completely ruin the engine. I just took apart the entire exhaust assembly from where the cat was. I’ve read it’s ok to drive without it but not for the long term. The thing is I don’t have anything else like a muffler, the pipe just ends right next to the transmission/drive-shaft. I would like to get a new cat and replace it but I’d of course need to drive to buy one. Honestly I’m scared to even turn on the truck bc of how it may perform. What should I do? Is it ok to drive? Btw it’s a 96 3.4 v6