My suggestion: look for a cheap second hand Xbox One X (not the Series X), I've got one and it's awesome, there's a lot of 4K 60 fps and 4K 30 fps games for it, specially Halo. they look gorgeous on a big TV.

Some of the best 4K games on the One X (not in order):

• Halo 5
• halo master chief collection
• red dead redemption 1 and 2
• Portal 1 and 2
• Dirt Rally 2
• Project CARS 2
• Devil May Cry 5
• Destroy All Humans (remake)
• gears of war 2, 3, 4 and 5
• forza horizon 1, 3, 4 and 5
• forza motorsport 7
• fallout 4, 3 and new Vegas
• far cry 3 and 5
• L.A. Noire
• mafia 1 and 2 definitive edition
• mirror's edge
• Skyrim
• the Witcher 2 and 3
• crash bandicoot 4
• assassin's creed 1, 3, rogue, origins and valhalla
• Descenders
• Nier automata
• no man's sky
• Hitman
• powerwash simulator
• skate 3
• goat simulator
• resident evil 2, 3, 7
• rise of tomb raider, shadow of tomb raider
• Valkyria Chronicles 4
• all kingdom hearts games
• final fantasy x, xiii, and xv
• battlefield 1 and V
• biomutant
• crackdown (the first one, 3 is garbage)
• red faction: guerilla remarstered

And remember that as being a console, you can always buy physical games and resell them after you're done.

Also a lot of these are on game pass now