Its more a peace of mind thing. I have an emf meter but its a bit hard to really test if its effective because i dont have access to a faraday covered room or something so whenever i test ill get radiation from every which direction and the meter will pick up on it. I will say, however, turning your device to airplane mode will drastically decrease the amount of radio frequency emf like 5g. This i checked myself and there was profound reduction in radiation noise immediately, and when i would turn 5g back on the emf meter on radio frequency would go absolutely bonkers!

Also as an aside, you may want to start regularly grounding / earthing either with grounding mats or just by being in and touching nature so you can let earth's negative charge and free electrons neutralize any build up and accumulation of positive charge that comes from exposure to emfs.