Best Fast Stationary LTE Routers with SIM Card Slot for Smooth TV Streaming under PLN 100

Hello. I have a mobile router from Play. On speed test I get around 25 Mb / s of download. Movies on YT stutter, TV programs on TV also. Will it help if I replace it with an LTE stationary router with a SIM card slot? Will there be a faster and more stable connection and will the TV set run smoothly? It has cut once every 2 hours so it's just a weak modem and not stable. The amount I can allocate is a maximum of PLN 100, of course used. Thank you for your help, best regards.
Ps I am writing because I found a similar topic, but the budget was high there and from 2015.

And what is a mobile router in Play for a subscription? What location, which LTE Play band are you using? What are the signal parameters, speedtest in the evening? The budget of PLN 100 is too small to buy a stationary LTE router.

The router is Huawei E5377s-32. Chorzów city center, how to check it? Download 25 Mb / s?

Check if your E5377 works with http://www.mediafire.com/file/1yz26m6u8gfl16n/E5186_Toolbox_latest_v0.9.zip in this program you log in to it and show the signal parameters and BTS CID. It allows you to force a specific LTE band on the E5377, you check LTE2600, LTE1800, LTE2100 and LTE800 in turn. You show screenshots and from each of the speedtest bands. The idea of the E5377 for home use was a failure from the start.

It is only after work around 23 I will add. Will some stationary router help? Or change the provider to e.g. upc

Do you have access to UPC? It pays off to use LTE in Play in the pre-paid offer where the cost of a minimum of 100 GB for LTE is PLN 5/15 per month.