Where Can I get my new RAM installed

You can install the RAM yourself and that does not void the warranty. If you have trouble with the RAM and did not purchase it from Dell, then the RAM of course would not be covered by warranty. Also if you damage the computer when you install the RAM, then that would not be covered under warranty either. Now if you are not comfortable with installing the RAM, then any reputable computer shop can do it for you. Dell would only install the RAM if you purchased the RAM from Dell.

https://www.dell.com/support/manuals/us/en/04/inspiron-15-7567-laptop/inspiron-15-7567-service-manual/replacing-the-memory-modules?guid=guid-1f5023f5-9868-4aaf-a9f5-bfb400cd890a&lang=en-us

@dementor_kr

If you decide to install the RAM yourself, (or have a woman with good fine motor skills do it).... you'll need to be sure you have the right screwdriver.

Follow directions and be gentle.  If you go to a store for PC services, they will likely charge too much to install your RAM.  They might make you sign a waiver that they are not responsible for issues if they break it (because you are bringing your own parts).

Always be sure that if you use more than one RAM DIMM, that all DIMMS are identical.  Never use mismatched RAM.

I bought my computer screwdriver at a local store that sells PC hardware.

There are a lot of different kits on amazon.  Keep it cheap.  The perfect screwdriver is what you need (not a bunch of screwdrivers to work on phones/tablets).

https://www.amazon.com/Glarks-660-Pieces-Phillips-Assortment-Motherboard/dp/B01G2SZLOS/ref=sr_1_6?keywords=computer+screwdriver+screws&qid=1570316304&refinements=p_72%3A2661618011&rnid=2661617011&sr=8-6

For the most part, I would not trust a 3rd party to fix my hardware unless I know the vendor.  I wouldn't walk into a big-box store and use their PC services.  I've been building towers longer than most of them have been alive.