Google-sheets – I would like to select one cell and highlight different cells in the same Google Sheets

Maybe:

=averageif(A:A,"Male",B:B)

One can't have both data and a formula in the same cell. If you want B4 to change in response to changes elsewhere (and don't want to write a script), then B4 must contain a formula. Then the data (such as "4, 7, 8, 5H") must be elsewhere. In my example, the data is in A4 but it could be any cell. Here is the formula for B4:

=join(", ", split(regexreplace(A4, iferror("(?i)\b("&join("|", filter(E4:H4, len(E4:H4)))&")\b", ""), ""), ", "))

Explanation:

1. iferror(join("|", filter(E4:H4, len(E4:H4))), "") joins nonempty cells in the range E4:H4 into a regular expression such as 7|abc|5H
2. The regex is wrapped in word boundaries: \b(7|abc|5H)\b, so that 7 does not get removed from 7H, for example.
3. It is made case-insensitive with the flag (?i), so that 2h is treated the same as 2H.
4. regexreplace replaces the above with empty strings
5. The split-join operation takes care of empty places left after replacement. For example, if regexreplace produced 4, 7, , 5H then split-join will make it 4, 7, 5H.