not sure if you have an aldis near you, but they do have plant based protein mixes on sale once in a while for cheap, and it’s a huge tub.
otherwise try adding hemp hearts to smoothies or shakes, use soy milk as it is a higher protein plant milk. you can add things like raw cacao which is good for you, has no sugar, and about 4g of protein per 2 TBS. you can also try a powdered peanut butter in your smoothies. try to score a plant protein shake mix on sale, sometimes brands will send you free samples even. sorry if this seemed long winded. i am an ex lifter who is vegan and tried to have about 100g of protein a day back when i was lifting.