So for me, as I stumble and bumble my way through learning French (mostly through DuoLingo, hey), I'm often thinking about this issue.
Now-- on the surface of things, Modern English is almost exclusively comprised of German & French, and almost every word in these sentences are specific examples of such in terms of direct etymology. Which is a big part of why I've typically regarded French & German as my sibling languages. It's a nice, bright thought, anyway!
Let's take the modern English word "fight"-- WP claims:
From Middle English fighten, from Old English feohtan (“to fight, combat, strive”), from Proto-West Germanic *fehtan, from Proto-Germanic *fehtaną (“to comb, tease, shear, struggle with”), from Proto-Indo-European *peḱ- (“to comb, shear”).
My point is that there's so many ways to run with that over time... in any language whatsoever! Indeed, IIRC there was a "fisten" variation which meant an entirely different thing in earlier German.
But, "shear?" Yes, yes back in my schoolyard days, I wanted to shear my opponent like a little lost lamb, but... I don't think that's right.
So here's my point, assuming you've lasted this far. Modern German in fact split from modern English maybe around ~~800AD? And Modern French, around... perhaps slightly earlier than the Norman Conquest (1066), meaning that even though Modern English is absolutely PACKED full of French & German pronyms, we can't just assume they mean the same thing, anymore, as with the examples above.
It sort of breaks my heart, but it's just reality, non?
Speaking of disappearing dialects, this reminds me of what's currently and gradually happening with Portuguese.
Although both Brazil and Portugal speak Portuguese, the Brazilian Portuguese is way different from European Portuguese spoken by the latter country, in a similar fashion on how American English is somewhat different from British English (cab vs taxi, color vs colour, spoken "computeRR/wateRR" vs "computAH/watHAH" (here I'm exaggerating for illustration purposes), and so on). Portuguese examples include "moço" vs "gajo" (both are words for "young adult man", respectively Portugal's and Brazil's ), "moça" vs "rapariga" (both words for "young adult woman"; the latter, the European Portuguese variation, while being a common word in Portugal, is often seen as a swearing by Brazilian Portuguese) and so on.
However, with the international popularization of Brazilian influencers (such as Lucas Neto), Portugal is complaining about their kids starting to sound and speak Brazilian Portuguese instead of European Portuguese. Seems like Portugal is facing a reshape of their own Portuguese variation due to Brazilian influence.
Brazil itself has many dialects and accents. South uses "bergamota" while southeast uses "tangerina" to refer to tangerine. Northeast uses "macaxeira " and southeast uses "mandioca" to refer to cassava. Minas Gerais uses "trem" and São Paulo uses "coisa" to refer to "thing" (e.g. "could you please reach me that thing over there?", a "mineiro" (people from Minas Gerais) would speak "ocê pega esstrem fazenofavô?" as a vocalized shortening for "você pega esse trem fazendo o favor?" while the paulista (São Paulo) would say "cê poderia pegá pra mim aquela coisa ali?" as shortening for "você poderia pegar pra mim aquela coisa ali?"). As you can notice, Brazilian Portuguese itself is so broad and multifaceted across the country. Even the same state has its differences (e.g. the capital city of São Paulo says "sinal" while the interior of the state says "semáforo" for "traffic lights"; also, São Paulo says "lotação" while the interior says "circular" for "shuttle bus").
Internationally, non-brazilians learning Brazilian Portuguese often tend to learn the Carioca (Rio de Janeiro) dialect, because there are many influencers and internationally famous Brazilian people that are from Rio (also, IIRC, both Brazilian Olympics and Brazilian World Cup happened in Rio).
There are other countries that speaks Portuguese as well, such as Moçambique (Mozambique) and Angola. Their Portuguese variation is slightly different from both the European and the Brazilian, but I guess the same Brazilian cultural influence is also happening with Mozambican and Angolan kids.