You can search for disease names (e.g. Alzheimers), gene names (e.g. apolipoprotein E), official gene symbols (e.g. APOE), Ensembl gene IDs (e.g. ENSG00000130203) or protein symbols (e.g. P02649). You may also be able to search for synonyms and abbreviations for both genes (e.g. apolipoprotein, p94) and diseases (e.g. IBD). You can also search for drugs (e.g. ADALIMUMAB) and phenotypes (hyperlordosis), which will get matched to their associated diseases and targets.
You can choose to embed a search bar on your website which allows you to search in the Open Targets Platform. See more details in the relevant github issue.