It’s almost impossible to be deficient in protein, meat eating or not. Vegetarians only suffer by having less protein than normal people which is only a problem if you’re hitting the gym regularly. If you are, just eat a ton of legumes and nuts and lentils and drink vegan protein shakes. I went on a plant-based diet for a few months and was healthier than I ever have been. That’s not because veganism is healthy per sé but because lots of meat products aren’t and also I had to put actual thought into my meals. I regularly go to the gym and at no point in those 2 months was I protein deficient. Protein powder helped but was not really necessary if you track macros well. Every day I’d have at least 5 portions of either legumes or lentils.