I don’t know about other denominations and apparently funeral traditions differ in different parts of the country. As a Catholic, I’d either attend the visitation or the funeral but not both, depending on what’s most convenient. The visitation the day before is often at the funeral home. Sometimes there is a little service there or a rosary said. You can go, pay your last respects, leave a card for the family and speak to your friend. This visitation the day before (aka the wake) can be quick if you need it to. It’s like an open house. If you do attend the funeral the next day, there is probably a visitation just before the funeral service which gives you time to talk to the family. Once the funeral starts, well, Catholic funerals last about an hour if there is a full mass. If it’s just the funeral service, it’s much shorter. You don’t have to accompany the casket or ashes to the cemetery but it’s a nice show of support. Afterwards, there is usually a luncheon somewhere. It’s also nice of you to go to that and visit with the family.
Here in the Midwest we put money in the funeral card but I hear that’s a regional custom.
" I object to violence because when it appears to do good, the good is only temporary; the evil it does is permanent." Mahatma Gandhi
"This is the ultimate weakness of violence: It multiplies evil and violence in the universe. It doesn't solve any problems." Martin Luther King, Jr.