Check out example codes for "css grid-template". It will help you in understanding the concepts better.

Code Example 1

/* Keyword value */
grid-template-columns: none;

/* <track-list> values */
grid-template-columns: 100px 1fr;
grid-template-columns: [linename] 100px;
grid-template-columns: [linename1] 100px [linename2 linename3];
grid-template-columns: minmax(100px, 1fr);
grid-template-columns: fit-content(40%);
grid-template-columns: repeat(3, 200px);
grid-template-columns: subgrid;

/* <auto-track-list> values */
grid-template-columns: 200px repeat(auto-fill, 100px) 300px;
grid-template-columns: minmax(100px, max-content)
                       repeat(auto-fill, 200px) 20%;
grid-template-columns: [linename1] 100px [linename2]
                       repeat(auto-fit, [linename3 linename4] 300px)
                       100px;
grid-template-columns: [linename1 linename2] 100px
                       repeat(auto-fit, [linename1] 300px) [linename3];

/* Global values */
grid-template-columns: inherit;
grid-template-columns: initial;
grid-template-columns: unset;

Code Example 2

.item1 { grid-area: header; }
.item2 { grid-area: 
  menu; }
.item3 { grid-area: 
  main; }
.item4 { grid-area: 
  right; }
.item5 { grid-area: 
  footer; }

.grid-container {
  display: grid;
  grid-template:
    
  'header header header header header header'
    
  'menu main main main right right'
    'menu footer footer 
  footer footer';
}

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