Hi @nipzplays
Here's some information that should help:
* [https://download.lenovo.com/consumer/desktop_pub/aio_510_hmm_20170306.pdf|hardware maintenance manual]
This details the procedures to remove/replace the components in the AIO.
* [https://psref.lenovo.com/syspool/Sys/PDF/Lenovo_Desktops/ideacentre_AIO_510_23/ideacentre_AIO_510_23_Spec.PDF|AIO specifications]
According to the specifications the AIO supports up to 8GB or ram in two slots i.e. 2 x 4GB modules, but according to this well known [https://www.crucial.com/compatible-upgrade-for/lenovo/ideacentre-510-23ish-aio#memory|supplier] it supports 16GB i.e. 2 x 8GB modules.
As for the HDD the supplier also states that it supports a ''sata'' 2.5" 7mm SSD up to 4TB (4000GB) which you can use in place of the HDD
* [guide|744] guide.