Negotiating terms of Draft Minute of Agreement

I have been forwarded a Draft Minute of Agreement by my partner's solicitor regarding our proposed divorce.

I'm unable to afford a solicitor of my own.
There are a couple of details in the text which are not entirely clear to me.
However, I'm being asked to pay a fixed amount in child maintenance which I have been clear with my ex needs to be reviewed. I'm also being asked to fund half of the solicitor's fee, again which I have not previously agreed to do.

My questions are:

1. How do I decide (or who decides) how much I should pay in maintenance each month? My partner, her solicitor?
2. How should I establish how much money I need to live on each month? My intention was to contact the CMS and have them work out the figure then negotiate anything additional with my ex. I have regular contact with our two little ones who stay over at mine at least twice a week, more frequently during holidays.
3. Can I be forced to pay part of the solicitor's fee?
4. I work full time but would struggle to pay a solicitor. Is there free legal advice available?

Many, many thanks in advance for any insight offered here.
Harold

Do not under any circumstances sign anything like this without first getting legal advice of your own. This is drafted by your wife's solicitor. Your wife's solicitor acts for her, not for you. Therefore any document drafted by your wife's solicitor is going to be in her favour and your interests will not be considered at all. You really should take your own independent legal advice about this. A local Citizens Advice Bureau may be able to give some basic advice but you really need to have a solicitor look at this for you. You will almost certainly come to regret it if you sign without taking proper advice.

Thank you, David.
I think I need to begin with CAB and take it from there.