Work your way through the Genealogy tab on
https://www.irish-genealogy-toolkit.com/irish-roots.html and you will find info on most of the basic things. Neither Ancestry nor Familysearch websites have access to the Irish BMD images north or south, just older indexes with less info. The census records on both those websites link to the Irish National Archive ones, as can see above none of us have needed to use either when researching, though Ancestry would likely hint eg the census and Will as weblink collections + BMD index entries as construct. Gaffy has I suspect though utilised a sub to RootsIreland to find the baptism transcriptions on
https://rootsireland.ie/derry/online-sources.php and I used a sub to Findmypast to check out the Belfast Telegraph death notices, sister site the standalone British Newspaper Archive.
Many people construct their tree on Ancestry and tie things together there, one can add weblinks or custom sources eg to the BMD records. Personally I find the tree facilities on Familysearch more cumbersome and being a global tree there others can input to it both correctly and incorrectly.
can also explore the links on
https://www.whodoyouthinkyouaremagazine.com/tutorials/overseas/best-websites-for-irish-ancestors/https://www.whodoyouthinkyouaremagazine.com/tutorials/northern-ireland-family-history/If you are visiting in 2023 you can order up open and photograph the 1910 Will in PRONI as transcript is not online but stored there. Is the Probate year you need rather than the death year. Also the other two for
Lee Julia Anna of 38 Old Cavehill Road Belfast widow died 12 July 1937 Probate Belfast 11 October 1937 to Evelyn Lee spinster. Effects £29 2s.
Lee Julia Evelyn Anna of 38 Old Cavehill Road Belfast spinster died 9 September 1953 at Royal Victoria Hospital Grosvenor Road Belfast Administration W/A (limited) Belfast 23 February 1955 to Dorothy Tempest married woman. Effects £2338 5s. 1d.
Their other resources are on
https://www.nidirect.gov.uk/information-and-services/public-record-office-northern-ireland-proni/search-archives-online and you will need to get to grips with their eCat and think of what you want to look at with references to save time there
https://www.irishfamilyroots.com/post/researching-at-pronihttps://www.nidirect.gov.uk/publications/index-school-collectionshttps://www.nidirect.gov.uk/publications/guide-church-recordsFor example 1st Magherafelt records start 1771 so possibility of further progress there as well as the ones already mentioned and there are transcriptions as CR codes as well as the microfilms. The references CR3/13; D2725/6; D1926/1-2; MIC1P/450 MIC1P/460 are mentioned in the church pdf guide but I would want to see what they are and the date ranges.
In the eCat I would input CR3/13* in the box against PRONI Ref: with 50 results per page (rather than browsing) to bring up more details of each of the codes. CR3/13/A/1A = Register of baptisms 25 September 1813-7 April 1861. Adding the star asterisk brings up all sub entries.