No problems, we're here to help, and we've all made similar mistakes ourselves particularly when new to all this.

From the "search" button on the FreeBMD site, enter your target's name, in this case "Cutler" and then "Frederick T". The FreeBMD site is a bit temperamental, you must spell things exactly as it thinks you should, with no extra spaces etc (some sites are good at allowing for spelling errors, both now and historically when the records were first created, FamilySearch (LDS) being a good example of a user-friendly site).
Also you must always remember to use one of the "Type" filters, birth marriage etc. The FreeBMD site's own Help screen explains this.
https://www.freebmd.org.uk/search-help.shtml

Please also see my notes regarding using the FreeBMD site in that old thread I posted before, they should help you get to grips with the site.
For now it's probably best to not use any more of the site's filters, until you get used to the site and how it works.
Also be warned, sometimes the FreeBMD site sometimes "freezes" if it's too busy or "broken".

Does this help ?

You will recall that I asked for Ellen/Nellie’s birth date. This was in the hope of tracing her in the 1939 Register which can be searched on the Find My Past website. A number of searches were made using the information available and she was not found. As I said earlier I could only conclude that she had either died or not given her correct date of birth.
My next step was to search the Birth, Marriage and Death Indexes. We know that she was single up until she gave birth to Gwendoline Vera so this would give us a start date. We have her full name and you tell us that she was also known as Nellie so we have 2 possible Christian names to use in searches. We also know that her second name is Gertrude but would add that the index only included the initial for second names after 1910.
Initially I looked for the birth of Gwendoline Vera by highlighting Births, inserting Browning as the Surname, Gwendoline as the First name and Browning against Spouse/Mother Surname. This is the result:

Births Sep 1921
Browning Gwendoline V Browning Lambeth 1d 823

Apart from the date it also told us where she was at that time.

Next step is to look for a possible marriage and using what we know we highlight Marriages and fill the search boxes as follows:
Surname: Browning
First Names: Ellen G
Date Range first box 1921 and leave the other box empty.

The result - No marriages

Next we make a similar search changing the first names to Nellie G and we have the following:
Marriages Jun 1924
Browning Nellie G Dungate Dartford 2a 1399
Marriages Sep 1927
Browning Nellie G Cutler Hampstead 1a 1723

So there are 2 possibles and we check them.
First of all by clicking on 1399 at the end of first entry we find that the Groom was:
Dungate George E Browning Dartford 2a 1399

I then looked for him in the 1939 Register and here is the entry:
Browning Household (5 People)
40 West Street , Bexley M.B., Kent, England
FIRST NAME(S) LAST NAME(S) DOB SEX OCCUPATION MARITAL STATUS SCHEDULE SCHEDULE SUB NUMBER
George E Dungate 04 Jun 1882 Male Painter & Paperhanger Married 51 2
Thomas Browning 25 Apr 1860 Male Builders' Labourer Retired Widowed 51 1
Nellie G Dungate 08 Oct 1895 Female Domestic Duties Unpai Married 51 3
Sorry, this record is officially closed. Check if you can open a closed record.
Kenneth E Dungate 12 Dec 1934 Male Under School Age Single 51 5

From this you will see that the date of birth Nellie did not match but the head of the household was Thomas Browning so needed further investigation.
First of all there is a matching birth for Nellie G:
Births Dec 1895
Browning Nellie Gertrude Dartford 2a 462

and she is with her family living in Bexley, Kent in 1901 Census:

Household Number Name Relation to Head Age Estimated Birth Year Gender Birth Place
106 Thomas Browning Head 41 1860 Male Blendon, Kent, England
106 Elizabeth Browning Wife 40 1861 Female Wickham, Kent, England
106 William Browning Son 8 1893 Male Bexley Heath, Kent, England
106 George Browning Son 6 1895 Male Bexley Heath, Kent, England
106 Nellie Browning Daughter 4 1897 Female Bexley Heath, Kent, England
106 Maud Browning Daughter 2 1899 Female Bexley Heath, Kent, England

So we can eliminate this marriage and we move onto the second one. Again we establish the Groom by clicking on 1723 at the end of the line and get:
Cutler Frederick T Browning Hampstead 1a 1723

My next step was to try to find them in the 1939 Register but no luck so I then looked for a possible death using FreeBMD:
Highlight Deaths and fill the boxes as follows:
Surname: Cutler
First name(s): Nellie G
Date Range: First box 1927 (this was the year they married) and leave the second box empty.

This produced:
Deaths Sep 1936
Cutler Nellie G 39 Hendon 3a 357

We know that Ellen/Nellie was born 1897 so add 39 and we get 1936.

There is also a search facility on the GRO (General Register Office) website and if we search for the death there we find her second name:

Name: Age at Death (in years):
CUTLER, NELLIE GERTRUDE 39
GRO Reference: 1936 S Quarter in HENDON Volume 03A Page 357

I hope that helps you and if you decide to order any certificates you can do so online at: https://www.gro.gov.uk/gro/content/certificates/default.asp

All the information you need is contained within this post.

Finally I searched for any possible children from the marriage but did not find any.

Mike

Frederick Thomas Cutler, age 34, Bachelor, builders labourer, Father's name Charles Cutler also builders labourer.

Nellie Gertrude Browning age 30, spinster, no profession, Father's name Arthur Browning who was an ex collier.

Witnesses were Charles Cutler and Edward Frank Ruel.