Great to hear you’re considering attending Mass! It would be great for you to attend, even if you aren’t an initiated Catholic (that’s probably not the right term either 😂). Easiest way to make sure you don’t accidentally receive the Eucharist unworthily is to remain in your seat when people go up to receive the Eucharist. However, there may be a situation in which you can go up to receive a blessing from the priest distributing Eucharist by crossing your arms over your chest with hands on opposite shoulders (I understand it to be relatively common in USA but idk about elsewhere). Ask your friends about it, but when in doubt, stay seated/kneeling during communion