unpopular
Been spending a lot of time on here!
Being protestant whenever I've been to a Catholic service or wedding I didn't know what was going on half the time anyway - but in my experience you don't take communion, you don't use the kneeler, if you're not Catholic. It's been long enough that I can't remember if I stood when everyone stands but I'm thinking probably yes.
As a Mormon kid going to Catholic school, no you DO NOT take communion. But the kneelers? Unfortunately yes. Many Wednesdays with sore knees while daydreaming about the church being a castle with knights and crowns and stuff and imagining little mice delivering the Eucharist directly from God through the tabernacle.