If you are at home and all washed up, and everything in your house is assumed to be covid free then you don’t have to worry. It’s not like every time you touch your face you have to wash your hands again. If you might have covid or some other germ on your hands that can make you sick, then you need to wash your hands before touching your face.
If you are in a public place, assume every surface has germs on it. So, if you touch a door knob or a payment pad at a store, your hand now possibly has covid or flu or a cold, and so you need to wash your hands before touching your face.
If you want to keep others safe, then you can wash your hands before you touch anything other people might touch.
Covid on your hand does not make you sick, covid that touches musous membranes like your eyes, nose, and mouth, that is what makes you sick, so if you move the virus from your hand to a muscous you infect yourself.
When you wash your hands make sure you suds up well, wash top and bottom, inbetween fingers and don’t forget your thumbs.
I have a table where I keep things that might have covid on them. Like mail I just picked up or new pantry items from the store. I let them sit for three days before I put them away. Don’t forget when you come into your house if you tough doorknobs and light switches those now possibly have covid, so you can wipe them of with sanitizing wipes or an alcohol pad, so your surfaces are clean and you don’t have to obsess about what you touch in your house.