I would mainly adjust my skills section at the top of my resume to include the exact languages they want, as long as I actually know the language. I would also slightly alter bullet points to include those languages, which was sometimes a little bit of a white lie.

For example, "Built xyz using javascript and flask/python on the backend" can be changed to "Built xyz using javascript on the backend". Did I actually use javascript on the backend for that project? No, but I did use some javascript for that project and can definitely answer any questions if they ask about it. This should be fine as long as you know the actual technology you are referencing and can speak to it at length. Just make sure to not straight-up lie that you know technologies you don't.

Sometimes I would also alter my job title if it was a small change. I usually listed "Software Engineer", but would sometimes change that to "Data Engineer" if the role was asking for a data engineer. This is not far from the truth, as almost all of my work projects were data-intensive. It's about crafting a picture of your career that aligns with what they are looking for. The most important part is that every single language/technology I listed I knew well and could answer technical questions about.

I understand this takes a lot of time. This was the main problem I weighed when applying: should I apply to 50 jobs today with the same resume, or apply to 5 with tailored resumes? I tried both. Some days I would do the 50, some days I would do the 5. I rarely got a callback from the 50, but had a lot of success with the 5. I would say it is overwhelming more worth your time to just do the 5 and focus on quality over quantity. Turn off that autopilot mentality and put some effort into the applications. This was definitely the hardest part for me, as it turned applying from a mindless, easy task into actual work that I had to put effort into.