You will miss out on all modern Minecraft features like the Nether update, deep caves, and new combat mechanics unless you use "backport" mods. Top Mod Recommendations for 1.7.10
If you are setting up a 1.7.10 world, these are some of the highest-rated mods from the community: mainkraft s 170 modami skachat
It has an estimated 4,000+ mods—more than almost any other version. You will miss out on all modern Minecraft
Minecraft "Greatest Mods of All Time" modpack for 1.7.10 & 1.12.2 mainkraft s 170 modami skachat