glitchy video in premier pro when adding video files shot on a sony camera - xavc s 4k files

Hi,

Completely new here and my mind is a bit blow from all the different file, types, names & advice seen on the internet ect. 

I shot some video footage on a sony a6700 and the files were save in xavc s 4k format, I had previosuly shot in xavc s-I 4k and could import the videos fine. However reading (maybe wrongly) shooting in xavc s 4k format can create better files to make a crisper/cleaner edit?!

However now when I try import the files to my macbook pro and into premiere pro (25.3.0) the videos are really glitchy and I can't watch edit them. Even when using beta version. 

It will accept the mp4 video file but rejects the .MXL file - But they are really glitchy in premiere pro and quicktime can't play them. I have tried adding the whole folder from the memory care and try to get the proxy files? from the sub folders but nothing appears...

Macbook Pro from 2020 so a little dated.

Processor - 2 GHz Quad-Core Intel Core i5

Graphics - Intel Iris Plus Graphics 1536 MB

memory - 16 GB 3733 MHz LPDDR4X

Is there a way of using these files or do I need to convert them into a different file type using adobe media coder 2025 - I just don't want to loose any of the quality which was the reason for using that file type. 

May have been a rookie mistake but i really need the files to edit and as best quality they can be! 

Any help massively appreciated. Sorry if it's been answered a million times already - There's just so much info out there my heads a jam! 

Thanks