Referencing a textbox value from a determined value to a textbox range

Apologies let me rephrase my question, as I don't think I'm doing it correctly.

I'm coding on excel vba userform.

As an example:
On worksheet:-

A1 B1 C1 D1
0-5 £100 5-10 £150

On my userform I have a textbox. I want to enter a value in the textbox and for that to link to a cell on the worksheet dependent on range.

So, if I entered 3.5 then this would fall between 0-5 (A1) and so £100 (B1) will be linked.
If I entered 7.8 then this would fall between 5-10 (C1) and so £150 (D1) will be linked.

Is there any code I can use to activate this command on my userform?

I tried to put code in but I'm not allowed to show html coding, which is what I have used for the email template.