Brand new user, someone help this noob

[Saya_Rose]

I am very inept in how to use anything with mods, please help me. 

 

I got Minecraft back when it first started and Notch was still in it. I played Vanilla before mods were a thing. I never got into mods, I joined a few public servers but never did anything on my own. I fell out of Minecraft for other games and years passed. Come recently I got back into it. I wanted to try some new mods and such. Well I come across Lucky Blocks and it says I needed to Download Minecraft Forge. I follow the link, click the newest version and see in the center the blue button Download Latest. I cant click it though. Underneath is the 6 things to click on, Changelog, Launcher, Sources, Installer, Mdk, and Universal. 

 

What do I click on to download the latest version? Then the mod says: Simply download with the button above and put the .jar file (without extracting) into your mods folder. Is that in the forge or in the game? Can anyone ELI5? I'm sorry if I sound dumb, I am just so confused. Thank you all who help!

[Saya_Rose]

Thank you for replying. I followed your instructions and got it done in the end. If you dont mind me asking, do i have to start a new game for mods to work or can they work on existing games?