I have had Norton and Malwarebytes installed on my computer for years, and they work in perfect tandem with each other--no interference as far as I can see. The Pro version of Malwarebytes can block malware attacks in real-time, whenever you accidentally or (intentionally) visit a malicious website. It's a great feature, but I would refrain from taking full-on advantage of it
If you're looking for a free antivirus, I would actually suggest looking into something paid. In my opinion, you do get what you pay for. On my computer I have managed to stick with Norton, only because that is what the factory had installed on it. Optimally speaking, my computer just seems to run smoother this way.
p.s. Last I knew, PRO version of MBAM is a lifetime subscription. If this is still the case, do buy it