Multiple "product issues" detected by google search console

[beturner2000]

Hi, 

My website is www.meyflycom. I received the below notification from Google Search Console today. Please note that my site is fairly new and I am learning as I go. This is my first website. So, I don't have a lot of technical experience with this.  Any help would be much appreciated. 

Search Console has identified that your site is affected by 7 Products issues:

Top Warnings

Warnings are suggestions for improvement. Some warnings can affect your appearance on Search; some might be reclassified as errors in the future. The following warnings were found on your site:

No global identifier provided (e.g., gtin, mpn, isbn)           I don't think I can have this because I sell t-shirts from Printful

Missing field "url"                                                                       Looks like it is there to me

Missing field "aggregateRating"                                              No clue. I am new, so there really wouldn't be any ratings yet but do I need to add this to my website or is this a google rating?

Missing field "priceValidUntil"                                                   no clue

Missing field "brand"                                                                   Looks like it is there to me

We recommend that you fix these issues when possible to enable the best experience and coverage in Google Search.

[Kaushal08011]

Looking for the answer on the same issue I am facing while inspecting my Product URLs.