Some of these pictures and descriptions may give away plot details that you might not want to know before watching the film.
This is a Netflix movie directed by Spike Lee about four African American Viet Nam veterans and one of their sons who return to Vietnam to find the body of the fifth member of their unit they buried, and to bring back millions of dollars of gold they also buried. Like most of Lee's movies, it covers a lot of ground. It's an a war movie, a road movie, a heist movie, a didactic African American history lesson, a study of the effects of war on African American soldiers who returned to a country that continued to repress them, and, for a few trivial minutes, it's a snake movie.
They start with a tour of Ho Chi Minh City led by a Vietnamese guide. He takes them in a boat to an open air floating market where we see a woman chop the head off a live snake, then hold it up to the men in the boat asking them if they want to buy it. She doesn't appear to have a kitchen, so she must intend to sell the snake whole to be cooked later. She dangles the snake in front of David (Jonathan Majors) the son of Paul, one of the four veterans. David acts like he's scared of snakes, and asks how you cook it. The guide tells him it tastes like chicken, but in the end niether he nor anybody wants to buy it. Did she really think a group of tourists would want to clean and cook a snake in their hotel rooms?
The market scene was probably shot in Thailand, so it's possible they used a real live snake that was sold for food there and really had its head cut off.
Then the guys hike into the jungle where they find the gold and their dead comrade, then everything goes to hell. It wouldn't be much of a movie without the double-crosses and killings we always expect to see when there is so much gold. A group of armed men show up and try to take the gold then a gunfight ensues and the armed men retreat. One of the veterans, Paul, (Delroy Lindo in a great over-the-top performance) argues his friends about what they should do next. When they disagree with his plans, he hikes off on his own with his pack full of gold. He hacks his way through the undergrowth with a machete until a snake falls on him, wraps aroud his arm and bites him. He struggles, screaming at the snake, trying to pull it off his arm. He finally throws it to the ground then shoots it into six pieces with an automatic rifle. (Too bad he didn't shoot that accurately years ago during the war when he accidentally shot and killed his friend which has haunted his dreams ever since.) We see two very large bloody fang marks on Paul's arm. He sucks the wound and spits, several times, cursing the snake. Then he carries on hiking without dropping dead immediately, as usually happens in movies. But soon he falls and rolls down a hill and his backpack full of gold is caught on a branch. Instead of trying to get the pack, he gives up on it and leaves it hanging, as if he doesn't care about it anymore, saying "Life is a bitch!" (I know that song. He left off the rest of the lyric - "and then you die." But that's coming soon.) Either the snakebite made him too weak to try to get the gold, or maybe he knows he's going to die from the venom and doesn't care about the gold anymore. Whatever the case, it wasn't the snake that killed him. Before the snake venom can do its work, he's shot about a thousand times by the thieves who were tracking him and found out where he was when he shot the snake. (He should have used the machete.) Some people are upset that Lindo did not receive an Oscar nomination for this role (the movie didn't either) but I think it might be because of this trite snake scene, which, for me, dragged down a very good movie. (And I'm a fool who enjoys snake scenes!)
I don't know what to make of the fact that the first snake scene involves the son David and the second one involves his father Paul. Or what is the significance of Paul being mortally wounded by the snake. (We know he's losing his mind, maybe he only imagined the snake.) Or maybe it's just because he's such an unlikeable man that he deserved a horrible ending. After all, he's a black man who voted for Trump and wears a MAGA hat! It's hard to feel sorry for Paul, but in the end he might be the only one of the four veterans who really understands their situation. His son David is one of the good characters in the movie, and he turns out to be a hero at the end in the inevitable third person shooter scene that happens in every action movie ever made.
The snake in the snakebite scene is mostly CGI with a prop snake probably used at times during the snake wrestling scenes.