You need to install the resource pack manager, download it here. Find a skin that you like in the gallery. Click on apply to minecraft button and select the file to replace. The texture will be saved on the novaskin resourcepack. Enable it in minecraft. That’s it! The new skin will be available in game immediately.What is the best Minecraft texture pack?
LUNA HD is one of the best realistic texture packs for Minecraft. To get access to the high-end packs you'll need to sign up to the team's Patreon, you can download the 32x pack as a taster and then sign up for higher resolutions. LB Photo Realism Reload (Image credit: 1LotS, Scuttles, GKrond, Misa)