“Looking jacked” and “getting fit” aren’t necessarily the same thing. You can be very fit and not look like an entrant in a body building competition. If that’s your goal, then no - just going to the gym and eating some protein is not going to be enough. Not being a Mr Universe type myself, I’m afraid I can’t offer you much advice on how to target specific muscle groups etc to get that appearance. I had an old housemate who had that lifestyle, so I’ve seen the process.

If you want to get fit, that’s a lot simpler (note I didn’t say “easier”). There are two things you do: move more and eat smarter. Of the two, your diet is the more important. For diet, the main things are (in order of importance and impact) stop drinking sugary drinks, avoid processed foods as much as possible and don’t eat more than your body needs.

Moving more is as simple as that - just move. You can walk, run, cycle, play sport - anything really that gets your heart beating. Don’t kill yourself overdoing it. Not only is that not sustainable, but it isn’t even that helpful. A daily 15-30 minute walk is better for your body and fitness than a single marathon effort that lays you our for several days after.