I love to cook with sous vide. My recommendation is to download the Anova Culinary app, or the Joule App, and just follow their directions for various recipes. Generally speaking it is so phenomenal on steak/filet that I won't cook those by any other method. I like it for pork steak as well because I can get it 'well done' for the wife, but still have it tender and juicy. In my experience, chicken is better using the traditional cooking methods. Chicken is tender and moist when cooked sous vide, but the texture is a bit weird and I've given up on trying to make it work. I might consider sous vide for chicken that is going into a noodle dish or something but I wouldn't cook chicken in sous vide to eat directly on a plate. I've also given up on trying to get multiple steaks to a different level of done-ness. It's just too hard to accomplish various levels for various steaks. If someone wants a different level of done-ness than what I'm cooking they just have to go somewhere else and get it.
The key to making it a success is in the sear of the meat after the sous vide completes. This takes some trial and error. I have found taking the steak out of the bag and setting it on some paper towels and pressing more paper towels on top gets a majority of the water off the steak. I then uncover the steak for a few minutes and let it get as dry as possible from heat evaporation. You want the steak as dry as possible before you sear it. I have a cast-iron skillet as hot as possible by leaving it on a burner on the propane grill outside for 30-40 minutes and I throw the steaks on the super hot cast iron. The cast iron is so hot that putting your hand a few inches above it is painful in seconds. I immediately surround the steak on the cast-iron with small bits of butter that basically burn off immediately, but enough gets under the steak to create a nice char (something about needing the milk fat in butter to create a char). Whenever possible I use unsalted butter as that seems to burn less. If you do this inside, be prepared for every smoke alarm to go off. NO MORE than 30 seconds on each side will create a super char. I sometimes hold the steak vertically with some tongs to sear the fat on the edges as well. It's very easy to sear a medium rare steak to well done if you go longer than 20 or 30 seconds on a side. There is no need to let the steak sit for 5 minutes like traditional methods (it does not continue to cook further when you take it out like it does on the grill or oven). I have found that the steaks are so tender and juicy, and that the done-ness of the steak is more edge-to-edge than traditional cooking methods. This edge-to-edge uniformity of done-ness makes the person eating it to interpret it as less done than they are used to (i.e. a well-done sous vide is slightly pink from edge to edge, but the person is used to only a small sliver of slightly pink in the center when they have traditionally cooked steak, so they interpret it as 'more pink' than normal). I've also found that the steak is so juicy that the plate fills up with juice immediately when the steak is first cut. My last tip is that immediately after searing, I perform 5 or 6 slices of the steak before I put it on the plate (so that the juices escape on the cutting board and do not flood the plate)