be warned that TV's will rarely ever be able to play movie video files you downloaded on your computer natively.
Your best bet is to just use your laptop.
Honestly though, for travel purposes, I think you need to evaluate what size and weight requirements you have. If you can ditch the laptop completely, your luggage will benefit. What I have ended up doing, is just loading movies on the internal storage of my phone (Pixel 6 Pro 6.8" screen size) and just play movies on my phone. Bring a little phone stand to help hold it for viewing.
If you can bump up a little in size, a recent model iPad could be used instead.
In both cases, you could also use an "OTG" USB Flash drive (important that the drive is listed as "OTG" On The Go and rated as compatible with iOS / Android) and plug it into your phone; Android and iOS should both be able to play movies this way with something like the VLC app. Note that most "normal" USB Flash drives will not work with mobile devices due to their higher power requirements.
On previous trips in the past, I just dug up an older Android phone with a large-enough screen plus microSD card, and loaded that with movies and used it as a dedicated movie-player.
There are a lot of options, ultimately it depends on how exactly you want to watch the movies, what screen size is acceptable to you, and how much extra luggage you are OK with taking.
One other thing I do a lot for travel, is to bring a "Chromecast with Google TV" with me
This device has an advantage in that you can set it up at home, log in to all your streaming services ahead of time, then when you reach your destination, you only need to plug it in and connect to Wifi and have access to your streaming content. Downsides include; requires a separate power cable that might not be long enough to reach the hotel TV, requires Wifi connection and streaming, not sure if its possible to play movies from USB drives. But, for the gf and I, this device has been perfect for a ton of AirBnb stays.