install memory in mac mini

Depends on what year model Mac Mini you have.

see > Upgrade or install memory in your Mac mini - Apple Support

For Mac Mini RAM upgrades,

go to > https://eshop.macsales.com/shop/mac-mini

or > https://www.crucial.com/upgrades/apple/mac-mini-models

As I may have to replace the memory soon in my 2010 Mac mini, I've researched this. The only vendors I would use is OWC (macsales.com) or Crucial (but OWC has wider selection of compatible RAM).

OWC are dedicated Mac people.

Tip: If you need to open the round plastic bottom of a Mac mini, use a silicone potholder or silicone sheet as a grabber, this makes it easy.

No one can possibly know the answer to your question because you never said which Mac mini you have, or how much RAM you want to add.