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### 1st issue

As others have said, `echo "$array"` only prints the first element of the array; I suggest

    printf '%s\n' "${array[@]}"

to print each element on a line.

### 2nd issue

More importantly, **the loop is partially incorrect**. Consider this file:

```
pear yellow
   apple \\ red   
orange brown    
```

<sup>Look closely: Lines 2 and 3 contain trailing spaces.</sup>

That's what the array gets (using underscores as delimiters to better see exactly what each element contains):

```
$ printf '_%s_\n' "${array[@]}"
_pear yellow_
_apple \ red_
_orange brown_
```

1. All the leading and trailing spaces were mangled. Address that with an empty [`IFS`][1].
2. `\\` became `\`. The [`read` command interprets backslash sequences][2], add the `-r` flag to disable that.

### Solution

```
while IFS= read -r line; do
    array+=( "$line" )
done < file
```

or, better, as suggested by r~~, use `mapfile -t array < file` (`mapfile` and `readarray` are synonyms). It is a single command and thus more efficient.

### Caveat

Finally, mind that shell loops are very slow. A test on a 10 MB file:

```
$ wc < /var/log/kern.log.0
  117555  1389245 10000045

~$ time { mapfile -t a < /var/log/kern.log.0; }
real    0m0.060s
user    0m0.052s
sys     0m0.008s

$ time { while IFS= read -r line; do b+=("$line"); done < /var/log/kern.log.0; }
real    0m0.720s
user    0m0.652s
sys     0m0.068s
```

And that is just reading the file into an array and doing nothing with it.

If attempting to process text, use actual text-processing tools (Awk, Sed, Jq, 
Csvkit, etc. depending on the task).

### Further reading

- [BashFAQ/001: How can I read a file (data stream, variable) line-by-line (and/or field-by-field)?][4]
- [Unix SE: Why is using a shell loop to process text considered bad practice?][3]
- [Unix SE: Why is `while IFS= read` used so often, instead of `IFS=; while read`?][5]

[1]: https://www.gnu.org/software/bash/manual/html_node/Word-Splitting.html
[2]: https://www.gnu.org/software/bash/manual/html_node/Bash-Builtins.html
[3]: https://unix.stackexchange.com/questions/169716/why-is-using-a-shell-loop-to-process-text-considered-bad-practice
[4]: http://mywiki.wooledge.org/BashFAQ/001
[5]: https://unix.stackexchange.com/questions/18886/why-is-while-ifs-read-used-so-often-instead-of-ifs-while-read