Hey Rabbi, I look everywhere on the internet and still I cannot find a definitive list of things one is prohibited from doing when Tamei (as a result of male discharge, menstruation, carnal relations, contact with a corpse, among other events). I understand that this is commonly interpreted as not being able to partake in certain activities in the Beit HaMikdash, but since that is no longer standing, how does this translate into present Jewish life? Is one prohibited from certain activities at Synagogue or wrapping tefillin, or is it not as relevant as I am making it out to be? F.Y.I. If this helps, I am a Levite, but not a Kohen.

Shalom and blessings, You are correct that since we are all considered ritually impure due to contact with the dead, this status has no practical implications in our times. Our Sages instituted that following a seminal emission, one should immerse in a mikveh before prayer and Torah study. However, in practice, this enactment was later rescinded, as it proved to be a decree that the community could not uphold. Nevertheless, it remains an act of piety to immerse in a mikveh before prayer and Torah study after a seminal emission (see Shulchan Aruch, Orach Chaim 88).