Doubt anything you read in pop culture health articles, especially those that emphasize "natural" or "holistic". Often even the more credible articles misinterpret the actual studies they cite.
If you Google "overdosing on vitamins" most of the links that come up are pop culture, wellness and pseudo-science hucksters. Many other links will be to mainstream media sites that lend an unwarranted veneer of credibility -- but few news outlets bother to hire full time medicine and science reporters anymore. So it's likely the TV network or mainstream news outlet just tossed the publicity release to whomever was available and they rewrote it without doing any fact checking. (I was a reporter years ago and that's pretty much par for the course, although our major daily paper did have a medicine/science reporter who had some training and credibility.)
Check any pop culture articles against the sources on PubMed and comparably credible sites where researchers publish. Those full reports can be a chore to wade through but the abstracts and conclusions are usually easy to understand. The data in between can be indecipherable to most of us and easily taken out of context.
In fairly recent years there have been papers contradicting previous claims about "overdosing" on certain vitamins. Bad info I'd read decades ago about taking "too much" vitamin D misled me into doubting my own doctors. Turns out that due to my own unique health issues (auto-immune disorder, thyroid cancer, wonky parathyroid, etc.) my vitamin D, calcium and immune system were dangerously deficient. My doctors prescribed 5,000 IU of D daily, which seemed like a lot. So I just took a multivitamin which had maybe 200-500 IU. After a year or so of continued low vitamin D and related factors my doctor phoned me in early 2020 to remind me to take it because it might help my immune system against the coronavirus. That persuaded me.
I've been taking around 5,000 IU of D in pill form, and whatever else is in my diet including milk, which I resumed drinking last year for the first time in decades. My lab work was back within normal range.
And that's the important part often overlooked -- lab work and medical advice. In my experience (including working in health care) it's pretty unusual for medical doctors to specifically recommend certain vitamins. Usually they just say eat a healthy diet. (It's different with osteopaths, some of whom do promote more supplements, or at least may be more specific about dietary practices.) So if an MD recommends or prescribes specific vitamins and supplements, it's a safe bet the patient needs them.
But it can be hard to know whom to trust. Linus Pauling got it wrong with his claims about massive amounts of vitamin C producing miracles. His late career wackiness overshadowed his earlier credible accomplishments. And when the coronavirus pandemic hit last year I heard a lot of claims about taking massive amounts of vitamin C and zinc, without any evidence those work.
Then we get into the whole issue of bio-availability and which food sources are more effective at providing nutrients. That's a whole nuther can of worms that caused me to give up on vegan and vegetarian diets and not only resume eating meat but a lot more of it. I can only say I feel a lot better now. There may be genetic predispositions affecting why some folks thrive on vegetarian and vegan diets and others don't.