It's really easy to remove the "sort by" filter. Just follow the steps:
1) Login to your store
2) Go to ONLINE STORE > THEMES > CUSTOMISE
3) Go to COLLECTION PAGES from the drop-down menu (check screenshot 1)
4) You'll find the option in the left sidebar for "collection pages"
5) Un-check the option "enable sorting" (check screenshot 2)
And it'll be done!
If your query is answered, please mark it as "Accepted Solution".
Thanks & Regards
One more suggestion, your header is too big, the scroll area is too limited because of that. It would be great if you make the logo a bit smaller.
we tested it on one of our sites, it can be done please check it here: https://7l3uiezrestt5kz0-1894121547.shopifypreview.com. is that what you need? if yes, then a bit of code is to be written in the liquid file, we'll do it.